A chain is already initialized, and the first programming of the PROM worked.
If the "mcs" file is updated with the same name, the first attempt to re-programmed the PROM with the new "mcs" file generates errors.
At the second attempt, Impact crashes.
This issue is fixed in 8.1i sp2 of the Design Environment Tools.
To work around this issue:
1. Update the "mcs" file with a different name.
2. Before assigning the updated "mcs" file, delete the chain and initialize it again.