...this is what a postcript ends up doing anyway, any vector elements below transparency will get rendered to pixels, the same is true for indesign or quark to postcript or exported to 1.3 pdf...
...this also explaind the golden rule of keeping vector on top layers as much as possible, particularly body text...
That's correct, but Indesign makes flattenig much much better than Corel.
...in acrobat 7 they all look fine apart from the CS3 created PDF...
...i'm not a corel user but in my experience the interaction it has with CS3 is bugged, as you are experiencing now...
...also, looking at your pdf files, the corel pdf is clearly RGB color, from indesign you are converting to cmyk via convert to destination profile i assume (whatever that cmyk profile may be), so you might want to be careful about what destination cmyk you are using here...
I allways make color conversion in Indesign, that's the way I'm used to it, because i have different color settings for different machines (offset, flexo...). Usually export Corel files in native format, sometimes also in RGB, so all the conversions are made in indd - usually, when text is placed over PDF in INDD.
...had a similar job a few weeks back using corel x3, with gradients and the lens effect tool, nothing but headaches. Symptoms were as you have posted (apart from the hefty gradient banding we experienced), drove us nuts...
That was the solution with indesign CS2. Exporting PDF v6 without compression, in native format. All the excellent work with flattening, converting to CMYK was indd's job. Allways perfect. Now, with CS3... Looks, I'll have to have one dedicated machine only for CS2...
...we ended up (after much head scratching) exporting to 1.3 from corel, all color conversion to cmyk in the pdf export from corel (as lens effects are always RGB it appears), we avoided the import to any other program...
In Corel X3 all effects can be defined as CMYK.
...out of interest, does the corel 1.6 pdf you have rip in apogee as you see it in acrobat 8 (all shadows shifted)??
Unfortunatelly I have Agfa PDF Rip v2.0 series 2 - machine is Avantra 30 - CTF. It doesn't support PDF files with transpareny. But on the other hand, Colorproof XF works with "Source" file without any problems.
I still believe it's Adobe's bug.
Primoz