Citrix Receiver for Windows 3.0

Unfortunately not through the end client, this is a setting which should be setup by whoever manages the Citrix server and is quick change to make.

Start-> Administrative tools-> Terminal Services Configuration -> Connections -> ICA TCP Properties -> Override user settings -> Disconnect from session.

From here, select override and select a time limit before disconnected sessions are ended.

This should stop any issues caused by users not closing Citrix sessions properly.

Yes - Xenapp works with both forward and reverse proxies. Citrix offers their own reverse proxy system, Netscaler, and there are other vendors that offer reverse proxies that work with Xenapp (Radware, F5).

With that said, addition of proxies complicate the Xenapp deployment. So an improperly configured deployment could easily break the implementation. F5 has sample documentation in the form of a deployment guide that illustrates step-by-step configuration on the F5 and Xenapp. Perhaps your IT team can use that as an example? Otherwise, it's best to contact the proxy vendor and Citrix for support (get ready for finger-pointing battle).

One quick thought - i'd ask your IT team to verify the Xenapp config to make sure there aren't issues with routing or DNS lookups. It's fairly common for organizations that use split DNS to not account for the routing differences when accessing services from within the organization, especially if the anticipated use case is for users to access the system from outside the organization.