Slic3r Manual – Slic3r Support

If this manual doesn't the answer to your problem you can try several things:

IRC

Found on the irc.freenode.net server, the following chat rooms are often filled with people who can provide real-time help:

#reprap: Highly active community of the RepRap project with many users of Slic3r.
#slic3r: Slic3r chat room where Slic3r developers and users can give help.

RepRap.org Forum

A dedicated forum for Slic3r exists in the RepRap forums.

Issue Tracker

If a bug may have been found in the software, or you want to raise any other issue, you can post to the GitHub issue tracker.

Please make sure you've read the guidelines below.

Guidelines for reporting an issue

Keep in mind that developers are working on a volunteer basis, and the volume of requests related to Slic3r is overwhelming, so please understand that the most complete and clear report you make more chances are that you'll get help and attention.

There is a good chance that the issue, you have encountered, is already reported. Please check the list of reported issues before creating a new issue report. If you find an existing issue report, feel free to add further information to that report.
Include STL file and config.ini (exported from File -> Export config...) that can be used to reproduce the issue.
Include screenshots of the G-code preview demonstrating that the issue can be seen in the G-code and it's not caused by mechanical problems or by the firmware.
Specify Slic3r version (or commit number) and operating system.
Make sure the STL file is manifold (failure to repair a broken model is not considered a bug; we only deal with bugs reproducible with valid models).
Include one issue per report. If you encounter multiple, unrelated issues, please report them as such.

Guidelines for requesting features

Slic3r is a community project, and features are usually added whenever there is general consensus on them. Please start by describing your goal by showing a concrete case. Show G-code of a real case produced with current Slic3r and describe what would you like to improve and why. Put efforts into documenting this with pictures, G-code preview screenshots, close inspection.

After you're focused on why you can move onto ideas for how to achieve that goal. But don't invert the order and the efforts.