Run script on fail

There are many ways to do this, depending upon your configuration... probably the most "obvious" is to utilize an event handler.  There are several available in TestComplete including, but not limited to, "OnStopTest", "OnLogError", and "OnLogWarning".  Do a search of the online help documentation to understand how to implement these.

Additionally, within your automation, you could implement "try/catch/finally" logic to detect fail points and, when something errors out, handle the situation in the "finally" block of code.

There are probably other ways of doing this, but these are the two that are probably the most common ways of solving this problem.

If you need specific help in implementing these, please let us know and we'll see what we can do.