When I export my file to EPS, I usually check how it exported by importing it back into CorelDraw. When I do, all objects appear to come back in grouped together on one layer, named Layer 1. This is despite my original file having more than one layer, each of which has been re-named. There has to be a way to do this, doesn't there? I just don't see any such options in the EPS export dialogue, though. Or am I missing something really obvious?
The plane of existence has most, (by a huge margin) of Illustrator users saving their files as PDF. Again this is an Illustrator specific PDF not what you get when publishing from any other application and I believe they do this without thinking which is more than subtlety promoted by Adobe. The AI file format as the files become more complex quickly becomes near unusable by AI users so PDF is easier for them.
Unfortunately because of this behavior when Adobe users get a PDF a huge percentage of them immediately open it in Illustrator which is like dropping pebbles into the gears.
When I do billboards they send a template which I use and follow all the recommendations for color model/space, bleed and resolution. I then take all design elements except the template, group them and powerclip them with the template placed behind them.
In general the output is done via a RIP that rasterizes the file to a file specific for the RIP as the TIF format has a limitation that precludes the ability to print images physically large enough for the dimensions of the billboard.
Tried that too. Still did it similarly to importing . . . instead of keeping one of my layer names, placed those objects on "Layer 1", and then retained one of my named layers. Here's something I hadn't thought of though . . . I create my own "Guides" layer for various reasons (a bit more control) and I wonder if the fact that it has the word "Guides" in it's name is causing Corel to choke when it brings it back in. It's not just "Guides" in the name - I have some other words there too, but maybe that's what's causing the layer to be re-named?
Since there's already a native layer named Guides, I mean.
Do you know anyone who owns Illustrator? If so ask them to open your PDF and see.
Try without your own "Guides" layer and see what happens.