NetBoot, Macintosh Manager: Software Compatibility

We are using an application on a NetBoot client but it sometimes does not perform as expected. The software should be compatible with iMac and Mac OS 8.5.1. Can you explain?
Applications developed prior to the release of Mac OS X Server and Macintosh Manager may need updating to be fully compatible with Macintosh Manager or client NetBooting. As with any new software release, this is to be expected.

Apple has released a Developer Technical Note describing how to create "NetBoot Server-Friendly Applications." This note was published in February 1999 to assist developers in writing software that functions as well on a NetBoot client as any other computer.

The following Knowledge Base article can help you find the Tech Note mentioned here:

Article 24493: "Apple Tech Notes: What They Are, Where To Find Them"
Published Date: Feb 18, 2012