Here are a bunch of things that have solved my problems with the interactive dashboards (this assumes that you've done everything that Sage tells you to do in their knowledgebase and on the CRM community.
1. Restart tomcat server
2. IIS Reset
3. Check permissions on the CRM folders and the applications, change permission, IISReset and restart tomcat.
4. Remove java from the machine, reboot and install an older version of Java. IISReset and restart tomcat.
5. Reinstall CRM with the IIS Aliases option checked.
5. Remove java from the machine, reboot and reinstall CRM and let it install it's own Java. IISReset and restart tomcat.
6. See 5, except change the install location of Java to a non-standard location (ie not Program Files)
7. Prayer
I hope one of those is helpful for you. :)