[Plugin: WordPress Mobile Pack] WordPress mobile pack

I went through all the specified steps setting read/write access to the necessary folders but keep getting the same error, even after deactivating/re-activating plugin:

Critical WordPress Mobile Pack Issue

Not able to cache images to /myDirectory/mySite/web/blog/wp-content/plugins/wordpress-mobile-pack/plugins/wpmp_transcoder/c. That directory is not executable. Please ensure that the web server has write- and execute-access to it.

Not able to install theme files to /myDirectory/mySite/web/blog/wp-content/themes. That directory is not executable. Please ensure that the web server has write- and execute-access to it.