Preset name not saved with Ircam Verb & Spat

Steps:
1) A project using either Verb or Spat (both from Flux Ircam Tools) is saved with the FX-window closed
2) Close Reaper
3) Open Reaper (re-loads project automatically)
4) Open plugin
Bug: --> The plugin kept and shows correct parameters, but doesn't display the corresponding preset in the lower left or lower right section (but "--" instead, as if no preset were selected).

However, if the FX-window containing Verb or Spat is OPEN, when the project is saved and Reaper closed: When Reaper is restarted now (automatically opening the FX-window as well), the plugins show the preset name.

Since there are these conditions where it works, I guess the bug is in Reaper and not in the Ircam Tools.

Thanks a lot,
Klaus1234