Ok, you did all steps above including step four several times over manually using different keywords as suggested, Royal vegas, microgaming, microgaming casino, casino etc. After you did, 1) what did you find? and 2) what did you remove?
If you uninstalled the program and removed all the registries for Royal vegas and reinstalled the software it should be solved. "Unless you have a firewall blocking the program" Microgaming also uses "Thumpers" did you find one?
If there is several Microgaming software programs on your computer "you should have found the registries for those programs also during step four" this could be causing a problem, two programs can be conflicking with each other.
After cleaning your registry were all the Microgaming programs still running correctly.
I would also contact support of the casino again they should be able to run you through the process of removing all their software registry components from your computer, they know where they are located. If the person you talk to says they don't know how, ask to speak with someone in their tech department and they will know for sure.
I know this might be a stupid question, but do you do normal maintenance to your computer? Like sweep once a week and defrag, monthly. If not this can cause some problems.
One thing to keep in mind with Microgaming software it houses quite a bit of spyware, last time I checked over thirty, your spyware programs should be detecting these if not I would suggest Webroot.