With which versions of Vtiger CRM is PDF Maker compatible ?

At the time our extension is compatible with Vtiger CRM versions:

7.0, 7.0, 7.1, 7.2, 7.3, 7.4, 7.5.

8.0, 8.1, 8.2.8.3 and 8.4

We do not recommend running it on Vtiger 5.x and 6.x as these versions of Vtiger itself are very unstable.