Hi I have made my own version of label_region which was missing. Not sure how to post it in the relevant request area so will put it wherever this goes and hope somebody who needs it finds or somebody puts it where it is meant to be.
I have recreated it with 2 codes: region_label_alt.pro and blob_maker_alt.pro
It takes a fair bit longer than IDL to run, I was getting times of about 25 seconds on 512, 512 images. It outputs exactly the same results as region_label in /all_neighbours mode for everything I have tried it on. I imagine somebody more experianced could speed up the code, I already have a few ideas - the blob making function is recursive and moves between pixels and often checks one already visited which could be fine tuned. Not yet got the time to do so but hope to do soon.
As this is my first upload any and all feedback/ criticism is sought.