when i have a job with translens piece in it somewhere , i send the job to production manager it ALWAYS pops up another small box ,"items in this contain bitmap images" } then i have to check a box at what DPI i want . after i ckick that it pops up in the manager.
now if your does not do that ,before you send the file, try selecting THAT PART and raserizing it through the flybar at top of screen..it should send the file and print ok as long as THAT PIECE IS RASERIZED .dunno if you need to rasterize the whole image like the man suggested above ,but it makes perfect sense to do that ,im sure he would not have posted if it wasnt true.
sometimes when I use a lens to make something transparent and it doesnt work for one reason or another, I make a note of what all the colors are and just make everything those colors. If it is a image you could always do it in photoshop.
I had an issue similar to this a while back and it was because of a contour cut line in the file. It may not be the same, but it's worth trying.
In the transparent lens window, the hide stroke box was checked.
That worked fine until I had a contour cut in the file. Once I added a contour cut, it added lines back around the transparency items and printed them.
I separated the contour cut from the underlying image and the lines went away.
It doesn't make sense to me, but it worked.
Before sending the image to rip (I use the flexi rip/print), rasterize the transparent lens image and make sure "transparent" is checked. Important...make sure you don't have any "guide lines" on the lensed image or they will become part on the image. Choose what DPI you would prefer, and print. If any abnormalties show up in the print, go back (undo the original rasterize), repeat the same process, but choose a lower DPI this time. Sounds backwards I know, but the lower DPI will print a slightly more pixelated image, but no lines. Hope that makes sense!