although it cured the strange tile assignations previously referred to, it didn't cure (or it enabled me to see previously invisible !) strange effects !!
There is now a problem in that the tiles for (say) level3 are being painted with (called up from) tiles of the same name in the lower (level2) folder/directory !
It is suggestive of further problems in indexing and loop counters of the form (m,n) or (i,j) ??
dunno, I'm still investigating the hows&whys but thought i'd post a prelim heads-up ! there is also a prob that some tiles are painted with an absent (white flat) tile unless an "enabling file/tile" exists in a lower structure/folder/directory ?? I'll post more when I get get my head round it all
No prob, curious is all, just that it stops climbing Mt Everest to lower
levels !!

Malcolm.