What happens if you write the individual slices you wish to merge to
single-slice images (temp1 and temp2).  Does this resolve the problem?
If it does presumably you could write a .cmd file to do it automatically.
(Incidentally, the most recent release of SOM that I have hangs the
entire computer if you attempt ANY sort of merge - I am still using a
3-year old version which lacks many of the new features but is at least
reliable).
                Guy Cox
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