Synthmaster One - Partial Presets Causes Crash

[falcon14]

HI,
It's been a very long time since Ive posted anything on KVR so here goes.

I'm experiencing a crash when trying to save any kind of partial preset. This happens in vst and stand alone formats.
I can get to the save dialog and type in a file name but when I click save, Synthmaster One closes with no file saved (Stand alone, plugin, regardless of DAW). Tone2 Nanohost (VST2 , 64 Bit) does result in an 'unhandled exception error'. I've included GIF and a Screenshot of the error.

I'm not using any external waveforms or modified file locations in any way. It's a default installation and all file and folder permissions are as expected. The same happens on a different PC (both running running WIN 10 btw!).

Point to note - Synthmaster 2 works like a dream here, so I really dont understand what's wrong.
I've gone through support, with no joy, unfortunately.

Synthmaster One Partial Preset Crash.gif