I think this was originally from a support article:
Two options, change is global for all drop down items however it is machine specific so every user (install of HEAT) will need to make this alteration, You can define up to 200 as a maximum:
1. Launch AdvancedHEATConfig.exe from the HEAT directory.
2. Select the Registry entry of Common.
3. Scroll to the ODBC entry named MaxDropDownItems.
4. Enter the preferred value and click OK.
Use the following registry key as a push install based on Login script or have users manually enter the key/string value if they have proper rights to the registry.
Thank you SO much. That is exactly the information what I was looking for to help my users.