Problems creating PDFs for professional print

Not sure if this is the right place to ask, but I hope you can send me to the right place if this one isn’t. I have problems creating a PDF from XeLaTeX for professional printing.

How it all started: I’ve been working on a card game since quite some time now. I had a prototype printed months ago where I used Adobe InDesign to put all the elements of the cards together manually. It was a task cumbersome. long, repetetive and boring. With InDesign I made an export as PDF and the printing company printed it happily.

To make my life easier, I started looking around and learned LaTeX. Much (mostly passive) help from this community made me learn enough to build a tool that puts all elements of the cards to the right places automatically. And I do have a PDF document that looks fantastic to me. I took it to the printing company as I did the first time. But now they sent back a bunch of problems to be resolved. I could solve some on my own, but I failed on central points:

• All text should be turned into paths instead of embedding the font
• Text needs to be set to overprint
• Maximum ink coverage must not exceed 305%

While I was able to do the first thing in Adobe Acrobat on the PDF document I generated, I was unable to solve the other two problems on my PDF. For overprint I tried XeTeX & Overprinting and http://tex.aanhet.net/overprint/, but checking the document in Adobe Acrobat afterwards showed I failed to set text to overprint. For the maximum ink coverage I didn’t even find a hint, so I suspect I might be looking at the wrong place.

My original goal is to create a PDF document suitable for professional printing with LaTex or subsequent post-processing of the PDF I generated, e.g. using ghostscript. But I am not even sure that is possible. If it is, I am uncertain whether the right approach is to produce an RGB PDF from LaTeX and turn it into CMYK afterwards, or to produce a CMYK PDF in the first place and then process it further, if needed.

And, last thing: I am on a very tight schedule as I have set due dates after I sent the PDF to the printing company as I was a bit naive not expecting above problems. So if there is a short, manual way you know about to fix my generated PDF document using Adobe tools the way the printing company would like it, please tell me. I would also like to fix my LaTeX or add automatic post-processing such that no manual PDF processing is required.

Summing up my questions:

1. How do I fix the problems in my generated PDF file as soon as possible?
2. What are the tools (and if possible steps) to automatically generate a PDF document that fulfills the above requirements?
3. Where in the whole process do I turn things from RGB to CMYK best?