This is the infamous Band-in-a-Box "255-bar limit"—a known issue that has been documented on the PG Music forum for years.
The explanation: BiaB has a technical limit of 255 bars maximum per song (including choruses). If your track is 32 bars long, for example, then:

10 choruses → 320... (actually already pushing the limit), but the key point is that as soon as the total (bars × choruses) exceeds this internal threshold, the program crashes with exactly this type of error: "Access violation... write of address in bbw64.exe." PG Music fixed part of this bug in the Mac version ("Fixed: Access violation and program crash if adding a repeat to song that requires too many bars (more than 255)"), but the limit itself remains in the Windows version, and many users still run into it.

Possible solutions:

Stay under the limit: generate your track with a number of choruses that keeps the total under ~255 bars (so for a 32-bar track, a maximum of ~7–8 choruses).
Work around it by exporting and then looping in a DAW:

Generate the track with just one chorus in BiaB
Export it as a WAV file
Import it into a DAW and duplicate/loop the track as many times as you like (40 times, if necessary)
You retain full control and completely avoid the BiaB limit

Biab Audiophile 2026