There still seems to be a problem when opening old VEP7 projects which use MIR Pro (24, non 3D) in 2 or more instances. On my slave PC (running Win 10) the first instance loads fine (including firing up MIR Pro 3D 24) but MIR consistently crashes while the 2nd instance is loading.
The error message is "You opened a multi-instance Vienna Ensemble Pro project. Please save your project after successful conversion to a tabbed Venue project!" There is also crash report window which I have used to submit details.
My workaround is to remove MIR from all but one VEP7 instance, reload MIR and save each tab separately, then reload all the MIR tabs and re-save the rebuilt VEP7 project (which is now stable), but this is time-consuming for large projects.
Versions: VEP7 7.1.1406, MIR Pro 3D (24) 7.0.507