Update 18.11.15: Separate images for small tiles supported (just don't select one if you want to use the same.) Deleting a custom tile is now possible (just click delete :P)
Update 16.11.15: Startmenu items are not listed recursively, i.e., also startmenu subfolders are supported.
since Th2, Windows 10 allows for custom tiles via a visualmanifest.xml again. I created a small application that allows you to create custom tiles for any item in your startmenu. As this is completely native, jump lists and context menus are fully working and no other services are needed.
The app is extremely simple. It lists all your (root) shortcuts of your startmenu. Simply select one item (application target is then the location where the shortcut points to) and select an image. Hit save and you are done. Pin the shortcut as usual to your startscreen. The image is copied to the application directory.
If you intend to create tiles for apps like calculator, please consider the excellent tutorial given here: http://forum.xda-developers.com/show...3&postcount=53
The app requires administrator privelegs to modify the creation time of the shortcut (otherwise the tile won't be refreshed).
Download: http://www.motzek.org/MyTile-20160819.rar (Disclaimer: You are on your own. I take no responsibility for whatsoever. App requests highest available rights.)
Source: http://www.motzek.org/MyTile-Source-2060819.rar I am releasing this source under CC BY-NC-SA: "This license lets others remix, tweak, and build upon your work non-commercially, as long as they credit you and license their new creations under the identical terms." I.e. modify it, publish it with source for free and give me credit. Program is written in c# (2013). The rar includes the complete Visual Studio solution.
Icons mostly by http://dakirby309.deviantart.com/art...cons-280724102
Solution to MS Office applications:
It is not possible to create custom tiles for MS Office applications such as MS Word, Excel, etc. using this application. Somehow a custom tileimage in the corresponding visualelementsmanifest is ignored. However, it is easy to change the tile-images!
1) Navigate to C:\Program Files\Microsoft Office\Office15\LogoImages (For Office16, @razmth reports to look at C:\Program Files\Microsoft Office\root\Office16\LogoImages)
2) Replace the respective tileimages. You only need to replace the -100.png images for a medium tile! For example, simply change the WinWordLogo.scale-100.png with a custom MS Word medium tile.
3) Startmenu entry must be refreshed. Select the <NameOfMSOfficeApplication>.lnk in MyTile (it will point to something xlicons.exe). Click on refresh.
Note: The original visualelementsmanifest.xml must remain. If you change them via this app, the above workaround does not work anymore. Get them from some other office installation and copy them over. You can manually edit them (via, e.g., Notepadd++) to change the color or hide the name. Afterwards refresh (see 3).
An existing visualelementsanifest.xml in the target application root will be overwritten. An existing *filename*-mytile.png in the target application root will be overwritten.