There would appear to be a few limitations in the RootsMagic functions one can use when running under CrossOver. However, these are unlikely to be significant for most RootsMagic users and is an acceptable alternative to the second one here.
Note that the following is extracted from appends on the various RootsMagic forums and is believed to be correct as at RM 6.3.1.4 and CrossOver 13.2.0. The author has not necessarily investigated these issues in great depth. As always, if anyone has additional or better information, then that would be most welcome.
RootsMagic To-Go
This requires the use of a USB drive, first to create the necessary files and then to be used as a PC boot device. I'm not sure whether the first of these is possible with CrossOver, but even if it was, the second part would require a "proper PC".
Direct Use of Dropbox
RM 6.3.1.0 introduced 2 new functions that use Dropbox by storing files directly onto the Dropbox site. File>Save to Dropbox saves the open database file, whereas File>Backup>to Dropbox saves a backup of the open database.
When running RM under Crossover, these options do not appear, apparently because of limitations of the Internet Explorer package included in the RM bottle.
Note that there is a relatively easy way round this. Just use Dropbox in the normal way outside RM.
There may be other limitations, but these are the only ones I am currently aware of.