@johnlocke2342: That sounds like EXACTLY my experience (which would make sense, as this is the same edit3 version that I had troubles with in mkvmerge before). In working through the issue previously, I was able to get what appeared to be a SOLID/WORKING muxed version that displayed special characters properly using mkvmerge by changing the "Charset" setting from "Default" to "ISO 8859-1" (for Western Europe) under the "Format specific options" tab for your French_edit3 language track.
The problems emerged for me when:
1) I am probably one of the least qualified to verify if foreign language subs are displaying properly, or not (the ? marks in the French subs were a pretty dead giveaway)…so, I am definitely gonna need help with each of the languages to best troubleshoot the issue.
2) I had previously employed a similar tactic with some of the other tracks as I did with the French one (designating the Polish track as "ISO 8859-16" Central, Eastern and Southern European languages, for instance)…but my effort there seems to have been less successful.
What I can say is that mkvmerge is an excellent and FREE program, and while I am experiencing some difficulties at the present…this really SHOULD work! The fact that your French_edit3 subs appear to display WITHOUT issue as an external subs file under my MacOS X using VLC Media Player 2.0.8 (but do NOT when muxed using the default "Charset" setting in mkvmerge 6.2.0) suggests to me that issue may well be in mkvmerge's rendering of subtitle character encoding (at least for the French language)…but I would like to gather at least a little more data on this before contacting the developer.
@Feallan: See my updated post above for a couple additional DL sources, hopefully at least one of the three will work better for you! ;)
@yoda-sama: LOL, indeed!