I just installed SPlat. If I open an old X3 project (e.g. song_a) in SPlat that contains a RealStrat or RealGuitar plug, the project will play just fine, and will seem to save to another name (save as song_b), but then if I try to reopen the new saved file, I get a fatal error with no really useful info other than to say a plug failed. (A fatal error occurred in plugin ".") By trial and error, I found that if I remove all existing instances of RealStrat and RealGuitar, I can then save and reopen. If I get rid of all existing instances of RS and RG, then add a NEW instance of either one, I can save and reopen. Any ideas? 

Freezing the synth might help but then you wont be able to edit the tracks.

soens
Freezing the synth might help but then you wont be able to edit the tracks.

Depends what you mean by edit
 
You can always go in and add Fx, sends, PC modules, adjust volume & panning etc after freezing a synth.
You can do the same with a frozen track provided you've unticked the right options in the freeze dialog

soens
Freezing the synth might help but then you wont be able to edit the tracks.

Thanks, but I am not really interested in a "work around" - but rather wondering what happened. I find it odd that the old plug instance works fine in SPlat, but cannot be saved in SPlat, and that a new plug instance created in SPlat seems okay. Almost like a save path related to the old plug and X3 got lost somewhere.
 
BTW my "work around" in SPlat is to save the old plug settings as a preset, create a new instance of the plug and set this new instance to use the old plug preset and then change the the midi track associated with the old instance to associate with the new instance. Then I get rid of the old instance. This method is actually is pretty quick and easy, and gives me a fully-functional track that I can use as I normally would, and I do not lose any specific tweaks I made to the virtual instrument. 
 

weird, maybe to do with how they use the registry entries? dunno