Not all omfs are created or read equally and you can be lucky or unlucky.
as insomniac says, if your thinking of going the omf route you would be better off just exporting all tracks as wavs.
From memory there are a number of export options out of Logic/Pro such as FCP xml, OMF, OpenTL & AAF and each have their strengths and weaknesses.
Other than not converting track names, strangely enough, the old OpenTL format contains the most detail in a conversion to PTF.
Sure rendered wavs are the simplest and easiest way to get your audio to another format but that is no good if you still want to maintain individual clips, automation, markers, etc, etc.
If the OP wants to test a few formats he can contact me via the AATranslator web site and I'd be happy to run a few conversions for him eg;
OpenTL, OMF, AAF and/or FCP xml to a PTF