Only voices that are based on MOTIF XS internal waveforms can be read. Voice files created with user samples cannot be loaded.
It goes on to detail instructions for converting files by utilizing the Motif XF Editor VST.
In contrast, the MODX compatibility page makes no such distinction and seems to suggest that the MODX is capable of directly loading Motif XS data (.X0A, .X0V, .X0G, .X0W) including user samples & without any XF Editor conversion.
I've done a search here and haven't found any discussion of this apparent upgrade in the MODX over the Montage. Is this accurate, or merely an oversight in the design of the MODX's compatibility document? As a user of the XS, it would be great to know if I could so easily share my custom sounds with MODX users.