"I know where Poser's "export/import" menu is, I just needed the step by step instructions to export and import things to properly use for dynamic clothes."

Not sure this answers your question, but when i do it, and its a "true" dynamic cloth object, i turn off all settings in the export and import menu.

And always as OBJ format, and makes sure that the cloth fit the default pose of the character im using. So im sure that i always have a clean piece of cloth as a backup.

If i need to make changes to the character like increasing size, i simply do that in another frame, calculate the cloth and export it in the frame i like. 

Then ill delete the object and move all the changes that i made to the character to frame 1, and import the cloth that i just exported. So it will fit the modified character in frame one. 

A good idea is to save your material settings for the cloth item first to the library, even though it should apply them when you import it again. Some of the settings might not be correct, so you simply apply the material again from the library and then you can use the item as normal with all the changes saved into it as default.