In addition to what Sebastian correctly written above.
1. It looks like ingredients you use should not cause blooming problems due their nature. They may stillcause tempering problems if you mix them into chocolate when they are too cold or too hot.
2. The problem may be in the actual temperatures of chocolate during the tempering.
quote from your post:
"Re-cool to 83 I have tabled the chocolate on a marble slab and mixed it back in for this stage, and also cooled it in a cold room.
Warm to 89 for dark and 86 for milk chocolates."
Unfortunately these "rule of thumb" temperatures will not ensure correct temper in all situations.
Any changes in the recipe may require change of these temperatures.
I would suggestexperimenting with small batches of the chocolate (without mixing in the ingredients) that you have and cooling to different temperatures, making records and finding the best settingsfor the chocolate you have. I know that this is time time consuming (bloom doesn't show straight away) but if the chocolate comes out of moulds very well and looks good you are half way there.
3. Another possible issue is the temperature of moulds. If too cold or too hot they will couse chocolate to bloom even if correctly tempered.