When you say they are not available, for clarity are you clicking the images you want to merge with the right mouse button, one of the options given is merge, then either HDR or Panorama.
Can you get that far but the options are not there?
If not I'd verify that the upgrade actually happened or that you are not accidentally still using LR 5 which may have been left on your machine
When I installed my LR 6 Upgrade i still had LR 5 on my Mac, the icon in the dock was actually LR 5 not the new LR 6. Took me a few minutes to work that out as i assumed (incorrectly) that LR6 would actually replace LR 5, but instead it installed it as well.
Worth checking if you have not already done so.
In addition to what Steveatesh wrote:
Major releases are always left in place and can be used in parallel. The catalog will be copied and upgraded for the new version.
Make sure to mark at least 2 photos to have these new tools available.
Thanks a lot mate - that's it, didn't think at all!
Thanks pal, that was indeed the case.
thanks for the reply, it was the quick launch icon that hadn't updated so I was launching the previous version without noticing it!