For reporting security issues, please contact the Litecoin developers on the #litecoin-dev Freenode IRC channel or alternatively you can email us at contact@litecoin.org.
If the node is "stuck" during sync or giving "block checksum mismatch" errors, please ensure your hardware is stable by running memtest and observe CPU temperature with a load-test tool such as linpack before creating an issue!
Any report, issue or feature request related to the GUI should be reported at