Are you running the latest version of gPodder available via Maemo Extras?

gPodder does not do any mounting/remounting/unmounting, so your mount-related problems might be something unrelated to gPodder. Maybe dmesg gives some output that your card has problems and linux therefore remounts it read-only?

gPodder stores its configuration files in /media/mmc2/gpodder/gpodder.conf. You can edit it there. Currently, /media/mmc2/gpodder/ is the hardcoded path, but this might change in the future.