Both download and inventory run tasks timeouts can be changed from unlimited time to a specific time. This is done via the agent registry setting:
add RequiredLimit DWORD(time in minutes) HKLM\\Software\\Altiris\\Altiris Agent\\Plugin Objects\\Agents\\SMFAgent
1. minimum time for Inventory Rule task timeout is 10 minutes
2. minimum time for Download task timeout is 30 minutes
3. this is a limit PER part of the Task. For example the detection check has a timeout limit, then the download has a timeout limit, and the execution as well. The duration of the timeout starts over for each part.