I decided to rebuilt all MATE packages for current this morning. I simply remove all MATE packages on my VM and pull the latest changes from my (was) private branch and build the latest one. All sources are now use 1.17 version number, EXCEPT for one: mate-icon-theme-faenza. It's still under investigation from upstream since it failed during make dist-check. Upstream have decided to bring back mate-calc since it's ported to GTK3 now so i simply removed Galculator from my MSB repository.
All the binary packages for MATE 1.17 are now uploaded to slackware.uk and i have pushed my branch called 1.17-prep in github. You can use that branch to build MATE 1.17 from source. This is a temporary branch and changes for 1.17 will be force-pushed. Once mate-icon-theme-faenza reached 1.17.0, i will merge this branch to master branch and it will diverge from the stable branch: 14.2-mate-1.16.
Also, i'm planning to include a new package called caja-actions. This package was requested by one of MSB user and he created the initial SlackBuild for me. I reviewed it and decided to adopt it as part of my MSB scripts. It will get added once 1.17 is complete.
For those who have been using mate 1.17 from my binary packages, please make sure to use upgradepkg --reinstall --install-new to reinstall all binary packages which was built against latest current update per Jan 14.