Mark, not sure about the API question... Veeam Monitor is regular windows application, we do not handle screen refresh ourselves. Best would be to contact Citrix and have them troubleshoot this as the issue is obviously on their side. Thanks.
I installed the Veeam Monitor client on my Citrix server (Presentation server 4.5) and am unable to get it to work. Did you run the Full or the Client Only install on the Citrix server?
I ran the Client only install and after rebooting the server (which install requested for native SQL to take effect) I launched the client, went to options client setup and received error.
Michael, you may want to review GUI log files to see what happens at this moment, though if it does work on regular servers, then the issue should be on Citrix side.