I am just wondering when publishing a pdf it seems to lock the program from doing anything else. Can I open a different ditamap or a differenct topic and work on that while it is publishing or is it just wasted time until it is done?
Editor remains locked until the composition request is completed ... in "older" versions of Arbortext. For sure in 6.0 and possibly some releases of 5.4, Editor can "queue" a job with Publishing Engine. Once the work is bundled and delivered to PE, Editor returns control to the author. When complete, PE sends an e-mail (assuming it is properly configured, server-side).
I do not know whether this is supported in a non-Publishing Engine environment. Probably not.