I update kdenlive to 4:16.12.1-2 but it cruched with me project build on 4:16.12.1 How can I downgrade to 4:16.12.1
I tried reinstall from https://launchpad.net/~kdenlive/+archiv ... ive-master
but I don't know which file is suitable for my os - I have linux Mint 18 (64) ?

ok I finaly find on
https://launchpad.net/~kdenlive/+archiv ... /+packages
it was:
kdenlive-dbg_16.12+git201701200015~ubuntu16.04.1_amd64.deb

It should be this package:
4:17.03+git201701200017~ubuntu16.04.1
Since Linux Mint 18 is based on Ubuntu 16.04

By the way there is no 16.12.1 version to which you want to downgrade. There is only 17.03 which is from GIT (bleeding edge). You might want to search elsewhere for package downgrade. O just try what Linux Mint 18 has to offer: Version 0.9.8 - it's in their repos.