I too have been cursing Landesk for a few months but to be honest it has a big learning curve and I've learned the hard way there are many factors that cause these problems.
1. Having a firewall on (Windows or Antivirus)
2. Having hiberation on. Computers won't wake up or run jobs while in hibernation.
3. Batch files that require user input like running a "copy to" job and if the file is already there normally it wants the user to answer Y or N to replacing the file. The user never gets this prompt running a Landesk software distribution. You have to have a /y or /n in the batch file to get it to work.
The same goes for running a msi if its not completely silent then Landesk chokes, which might be your problem.
4. Last but not least is Desptop control programs that some of my users have that block jobs from running successfully.
I will say the biggest gripe I have is with documentation but it seems like lately they are keeping up with it.