I have made some bug fixes and performance enhancements to the Collapsed Topics and Weeks course formats. All versions are affected, 1.8, 1.9 and 2.0.
Please download and replace your version from the Modules and Plugins Database as follows:
Collapsed Topics - http://moodle.org/mod/data/view.php?d=13&rid=2307
Collapsed Weeks - http://moodle.org/mod/data/view.php?d=13&rid=2849
To upgrade, put your Moodle into maintenance mode, backup your existing topcoll and / or weekcoll folders in course/format, delete the contents of the topcoll / weekcoll directory and replace with the files within the respective topcoll / weekcoll folders contained within the zip files, put Moodle out of maintenance mode and continue as normal.
If you experience any issues, just reverse the process using the files you backed up, and then let me know
I've tested as much as I can, mainly on Firefox on both Windows 7 and Ubuntu, with a little testing using Internet Explorer on the 1.9 and 2.0 versions. Getting Moodle 1.8 running on Windows 7 is tricky, so I resorted to running on Ubuntu.
You can customise the look of the format using the instructions contained within the 'readme.txt' file.
Cheers,
Gareth