Hello David,
great work in that short time, my respect!
I tried the pro version and it works very fine so far. This quick test shows two issues for me which are worth to mention (beside the restrictions you mentioned above):

1. Scribble strips: After resetting the mixer all channels have no names stored but there are the default names displayed on the mixer ( e.g Ip1, Aux2 and so on ). You display just no name. Also you are currently show black instead of the default color of the channel by type (green for input, cyan for mixbusses....)
2. The parameters of the optional compressors (Opto, Mighty ...) are not shown correctly. maybe you need that plugins too, to handle them in the right way

Platform: Android
Variant: SQ