Right, I no longer think the problem is with EA Access. I am installing with the installer that came with it, and I downloaded it from IGN's Direct2Drive. The only thing I did before running Setup.exe using the "Install other game" deal, is install WindowsXP-KB942288-v3-x86.exe, because the "Leveraging Supported Software" sections said it might be useful. That didn't seem to affect the behavior.
Here are the log lines immediately before the few I pasted:
[Saturday Apr 24 14:12:51 2010] Setup Registry (Path, Flavor, GUID)
[Saturday Apr 24 14:12:51 2010] Adding file association [.dazip] [DragonAgeOrigins.dazip]
[Saturday Apr 24 14:12:51 2010] Adding Registry Key: HKCR '.dazip' '' 'DragonAgeOrigins.dazip'
[Saturday Apr 24 14:12:51 2010] Adding Registry Key: HKCR 'DragonAgeOrigins.dazip' '' 'Dragon Age: Origins DLC'
[Saturday Apr 24 14:12:51 2010] Adding Registry Key: HKCR 'DragonAgeOrigins.dazip\shell' '' 'open'
[Saturday Apr 24 14:12:51 2010] Adding Registry Key: HKCR 'DragonAgeOrigins.dazip\DefaultIcon' '' '"C:\Program Files\Dragon Age\bin_ship\daupdater.exe",0'
[Saturday Apr 24 14:12:51 2010] Adding Registry Key: HKCR 'DragonAgeOrigins.dazip\shell\open\command' '' '"C:\Program Files\Dragon Age\bin_ship\daupdater.exe" -file "%1"'
[Saturday Apr 24 14:12:51 2010] Creating Service: DAUpdaterSvc
[Saturday Apr 24 14:12:51 2010] Result: [DAUpdaterSvc] [C:\Program Files\Dragon Age\bin_ship\DAUpdaterSvc.Service.exe]
[Saturday Apr 24 14:12:52 2010] Ran Y:\Dragon Age\data\Dragon Age Uninstaller.exe
[Saturday Apr 24 14:12:52 2010] Result: 0
[Saturday Apr 24 14:12:52 2010] Create C:\users\Public\Start Menu\Programs\Dragon Age Origins\
[Saturday Apr 24 14:12:52 2010] Creating Short Cut "C:\users\Public\Start Menu\Programs\Dragon Age Origins\Dragon Age Origins.lnk" "C:\Program Files\Dragon Age\DAOriginsLauncher.exe" ""
[Saturday Apr 24 14:12:52 2010] Creating Short Cut "C:\users\Public\Start Menu\Programs\Dragon Age Origins\View Readme.lnk" "C:\Program Files\Dragon Age\docs\readme_en.txt" ""
[Saturday Apr 24 14:12:52 2010] Creating Short Cut "C:\users\Public\Start Menu\Programs\Dragon Age Origins\Uninstall Dragon Age Origins.lnk" "C:\Program Files\Common Files\BioWare\Uninstall Dragon Age.exe" ""
[Saturday Apr 24 14:12:52 2010] Creating Short Cut "C:\users\Public\Start Menu\Programs\Dragon Age Origins\EA Product Support Help.lnk" "C:\Program Files\Dragon Age\docs\EA Help\Electronic_Arts_Technical_Support.htm" ""
[Saturday Apr 24 14:12:52 2010] CreateDirectory "C:\users\Public\Start Menu\Programs\Dragon Age Origins\Web Links"
[Saturday Apr 24 14:12:52 2010] Creating Directory "C:\Program Files\Dragon Age\docs\Web Links"
[Saturday Apr 24 14:12:52 2010] WriteIniStr "C:\Program Files\Dragon Age\docs\Web Links\Dragon Age Origins Website.url" "InternetShortcut" "URL" "http://go.bioware.com/dragonage/pc/startmenu/community/en"
[Saturday Apr 24 14:12:52 2010] WriteIniStr "C:\users\Public\Start Menu\Programs\Dragon Age Origins\Web Links\Dragon Age Origins Website.url" "InternetShortcut" "URL" "http://go.bioware.com/dragonage/pc/startmenu/community/en"
[Saturday Apr 24 14:12:52 2010] WriteIniStr "C:\Program Files\Dragon Age\docs\Web Links\Support WebSite.url" "InternetShortcut" "URL" "http://go.bioware.com/dragonage/pc/startmenu/support/en"
[Saturday Apr 24 14:12:52 2010] WriteIniStr "C:\users\Public\Start Menu\Programs\Dragon Age Origins\Web Links\Support WebSite.url" "InternetShortcut" "URL" "http://go.bioware.com/dragonage/pc/startmenu/support/en"
[Saturday Apr 24 14:12:52 2010] WriteIniStr "C:\Program Files\Dragon Age\docs\Web Links\BioWare Website.url" "InternetShortcut" "URL" "http://go.bioware.com/dragonage/pc/startmenu/bioware/en"
[Saturday Apr 24 14:12:52 2010] WriteIniStr "C:\users\Public\Start Menu\Programs\Dragon Age Origins\Web Links\BioWare Website.url" "InternetShortcut" "URL" "http://go.bioware.com/dragonage/pc/startmenu/bioware/en"
[Saturday Apr 24 14:12:52 2010] WriteIniStr "C:\Program Files\Dragon Age\docs\Web Links\EA Website.url" "InternetShortcut" "URL" "http://go.bioware.com/dragonage/pc/startmenu/ea/en"
[Saturday Apr 24 14:12:52 2010] WriteIniStr "C:\users\Public\Start Menu\Programs\Dragon Age Origins\Web Links\EA Website.url" "InternetShortcut" "URL" "http://go.bioware.com/dragonage/pc/startmenu/ea/en"
[Saturday Apr 24 14:12:52 2010] Creating C:\users\Public\Desktop\Dragon Age Origins.lnk C:\Program Files\Dragon Age\DAOriginsLauncher.exe
[Saturday Apr 24 14:12:52 2010] Creating C:\users\crossover\Application Data\Microsoft\Internet Explorer\Quick Launch\Dragon Age Origins.lnk
[Saturday Apr 24 14:12:52 2010] CreateShortCut Failed
[Saturday Apr 24 14:12:52 2010] Game browser: check for old versions and remove them from the games browser
[Saturday Apr 24 14:12:52 2010] No previous games browser info.
[Saturday Apr 24 14:12:52 2010] Adding the games browser...
[Saturday Apr 24 14:12:52 2010] GUID: {B5E60645-6059-4E39-82E3-26B524D68A70}
[Saturday Apr 24 14:12:52 2010] GDF found: C:\Program Files\Dragon Age\bin_ship\DAOriginsGDF.dll
[Saturday Apr 24 14:12:52 2010] GameuxInstallHelper::AddToGameExplorer(t 'C:\Program Files\Dragon Age\bin_ship\DAOriginsGDF.dll', t 'C:\Program Files\Dragon Age', i 3, g {B5E60645-6059-4E39-82E3-26B524D68A70}) 39
[Saturday Apr 24 14:12:52 2010] GameuxInstallHelper::CreateTask(i 3, g {B5E60645-6059-4E39-82E3-26B524D68A70}, i 0, i 0, t 'Dragon Age Origins', t 'C:\Program Files\Dragon Age\DAOriginsLauncher.exe', t '') 0
[Saturday Apr 24 14:12:52 2010] GameuxInstallHelper::CreateTask(i 3, g {B5E60645-6059-4E39-82E3-26B524D68A70}, i 0, i 1, t 'EA Product Support Help', t 'C:\Program Files\Dragon Age\docs\EA Help\Electronic_Arts_Technical_Support.htm', t '') 0
[Saturday Apr 24 14:12:52 2010] GameuxInstallHelper::CreateTask(i 3, g {B5E60645-6059-4E39-82E3-26B524D68A70}, i 0, i 2, t 'View Readme', t 'C:\Program Files\Dragon Age\docs\readme_en.txt', t '') 0
[Saturday Apr 24 14:12:52 2010] GameuxInstallHelper::CreateTask(i 3, g {B5E60645-6059-4E39-82E3-26B524D68A70}, i 1, i 0, t 'BioWare Website', t 'http://go.bioware.com/dragonage/pc/startmenu/bioware/en', t '') 0
[Saturday Apr 24 14:12:52 2010] GameuxInstallHelper::CreateTask(i 3, g {B5E60645-6059-4E39-82E3-26B524D68A70}, i 1, i 1, t 'Support WebSite', t 'http://go.bioware.com/dragonage/pc/startmenu/support/en', t '') 0
[Saturday Apr 24 14:12:52 2010] Adding Firewall Exception 'Dragon Age Origins Game', path: 'C:\Program Files\Dragon Age\bin_ship\daorigins.exe'.
[Saturday Apr 24 14:12:52 2010] Unknown firewall error trying to add 'Dragon Age Origins Game', path: 'C:\Program Files\Dragon Age\bin_ship\daorigins.exe'. (Error, -2147221005, Unknown error)
[Saturday Apr 24 14:12:52 2010] GameuxInstallHelper::RegisterWithMediaCenter(t 'C:\Program Files\Dragon Age\bin_ship\DAOriginsGDF.dll', t 'C:\Program Files\Dragon Age\bin_ship\', i 3, t 'C:\Program Files\Dragon Age\DAOriginsLauncher.exe', t '', i 0) -2147467259
[Saturday Apr 24 14:12:52 2010] Direct X Version:
[Saturday Apr 24 14:12:52 2010] Express mode, install Direct X
[Saturday Apr 24 14:12:52 2010] Updating Direct X
[Saturday Apr 24 14:12:57 2010] Result: 0
The only error in that section is the Windows Firewall exception one, which I'm sure is not relevant. I haven't done the whole install DirectX seperately first thing, because that part of the process seems to have gone fine. The actions before I started this chunk of the log are just extracting stuff, and that all seems to have gone fine.
I spot-checked a few of the permissions, and everything seems to check out. Both installation files and bottle are in my user space, and I have write permissions to everything I checked. DataSetup.exe doesn't have execute permission, but neither do Setup.exe or PhysX_9.09.0408_SystemSoftware.exe, so I don't think that's a problem.