Nestopia saving problem

[Hikaru500]

Hello there, i got little problem with saving game on NEStopia
While press Shift + 1 to save, i got error "File not found"

I dont understand what file i need to save state?
Even ive got this error game saves anyway and can load by pressing 1

I wanna rid off this error but cant find any solution.

[jeruka9-san]

what version 1.40 or Undead Edition (1.46,1.47)
im was always savestate as file : savestate save as
im not use save slots
and most important qestion you play on windows or not newstopia was ported on linux