DS what do you mean by 'assertion error' ?
Sorry, I should have said Access Violation here.
For Example, here is the PCB Wizard bug:
Create a new PCB using the PCB wizard.
Set Boundary layer, in the first dialog box to: None
Pick all remaining defaults in all the remaining dialog
]: Re[2]: Re[2]: Protel / MSoft
SNIP
In my case, it appeared to do the copy, but it generated an Access
Violation in the process.
I was trying to copy and paste from the current PCB document, into a
New PCB document to generate a new rev of the (same) PCB
design, at the
time