Problems getting encryption (TripleDES) working

I'm trying to use encryption in NAV 2009 SPR (RTC), using instructions set out on Kertan's blog (http://mibuso.com/blogs/kirtangor/2010/ ... amics-nav/). I'm not having much luck yet though.

I have built the TripleDES.dll file according to the steps laid out in the blog entry, but I dont think it is getting registered properly. I have tried the usual regsvr32, but this didnt work. Eventually I used the line:

c:\Windows\Microsoft.NET\Framework\v2.0.50727\RegAsm.exe TripleDES.dll /tlb:TripleDES.tlb

which seemed to work better - it was now available to be used within NAV. I wrote my code (similar to that in the blog), but it wont work. In the RTC I get the message:

Retrieving the COM class factory for component with CLSID {8B3A39BA-5039-4248-A1FF-5455555400F8} failed due to the following error: 80070002.

When I run the same code in the classic client, I get the message:
This message is for C/AL programmers:

Could not create an instance of the OLE control or Automation server identified by
GUID={09B97DBF-A155-40B1-95DD-633D8672A9D3} 1.0:{8B3A39BA-5039-4248-A1FF-5455555400F8}:'TripleDES'.TripleDES.
Check that the OLE control or Automation server is correctly installed and registered.

I'm at a loss now. The dll has been registered on both the client and the service tier (they are different computers).

Any ideas as to what I'm doing wrong?

Thanks.