I am trying to use an image map on a prop, and the seam line runs right down the front of the item! Is there a way to rotate this seam line on the mesh? I have no idea since I don't model. No clue as to what software might help.

Anyone with advice?

would be very surprise if blender didn't come with an edit seam function.

You would need to remap the model in a modeling app or something like UV mapper. 

Of course once you map it, none of the previous images made for it will work on the new map. 

Blender has a decent UV map editor. About the best free one you'll find, but it takes some practice and getting used to it if you're not familiar with Blender's functions. 

Any experience with Wings3D? I find it's UV editor to be pretty robust. I think UV mapping is the most tedious aspect of making stuff for Poser (with grouping/ joint editing multi tentacled entities being a close second)... It's kinda like playing Dark Souls: frustrating as hell but pretty awesome feeling when you finally get it right. TBH I think that jumping the necessary hurdles in an image editor might be the path of least resistance.

Maybe modifying your original idea to incorporate a similar but more UV friendly prop is something to consider?

Second opinion...

Thinking about your problem you could try importing your object into UV Mapper Free and then exporting it back out with UV coordinates unchecked, this will strip the UV info from the .obj. Import stripped object into poser and use the group editor to create perspective UVs, a kind of planar mapping. I've never used this method so you'll have to do a little research or ask about on the forum some more. My understanding is that it's a primitive method to apply UVs to an unmapped object, entirely within Poser. Sounds like results will vary... I imagine the quality of the result depending on the complexity of the model (e.g. pretty decent with a one sided square. Not so much with a convoluted organically shaped object).

Second second opinion,

You might also want to think about Poser's flip UV coordinates function in the importer dialogue... although this can quickly turn into a game of backwards and upside down importing and exporting loop (your image editor is a speedy way of adjusting this to accommodate any weirdness). All of this is just thrown in the air conjecture without actually seeing the kind of object and related image you are using, though.

:)

Actually, I have found a work-around for my problem. :)

Thanks to all who offered help! I appreciate it!

after reading thru this whole thread, kinda interested what the workaround was?  lol

was gonna mention the createuv on the grouping tool.  

I used a procedural instead of an image. The seam didn't show with it.

procedurals the best!!

found the thread on the grouping tool uvs  http://www.renderosity.com/mod/forumpro/?thread_id=2772605#msg3455018

Thanks for tracking down that thread, misty... even though I'll never need that function, an interesting read nevertheless.

found it cuz i remembered bb had chicken pot pie for lunch that day lol