1. If you havent got the 206 rating already then ask them for the manual in advance so you can be on top of this part (or have not flown the 206L II, some differences/ engine and of course the instrument & autopilot fit which are different to the standard 206B - if possible, pop in and take a picture of the panel so you can stick it on your bedroom ceiling and practice the scan on the panel you will use 24/7)
2. RANT sim, as noted above. I dont think RANT has got Danish plates in it but if it has then practice on the ones used.
3. Get familiar with the local training area, approach plates for the airfields used and any unusual features of those fields (especially the effect of coastlines on NDB .......) [thanks, Madman, for the tip back then!]
4. See if you can think of anything to do in Billund at night (assuming it is BAS)