Doing the above causes a crash in Studio One 3.5 on Windows 7 64bits with Studio One running as a 32Bit application.
The idea is to instanciate the plugin once after the dll was loaded to extract its factory presets as a set of vstpreset files (using PresetFile) otherwise exposed via a means of a program list parameter. This is done in order to support VST3 presets in cases where the latter API is not supported, e.g. Studio One or Samplitude, but leads to the described crash in Studio one.
It’s also worth mentioning that the exception occurs outside of the plugin code and after the plugin has been unloaded in a module linked by Studio One:
The crash happens in cclgui.dll (read access violation at address 0x52C91EA0), which accoding to the description contains Presonus’ Cross-platform UI framework.
All other plugins and the code that actually extracts the presets have been removed so it’s definitely stripped down to this particular scenario. So far I’ve only observed this in Studio One.