I agree with skyesfury Masque is not working with Bartender or Raven.
Masque 5.0.387 is working fine with Raven, as far as I can tell. I use Masque: Renaitre skin, which is up-to-date. I also test with several other skins. Please try to be as specific as possible when reporting bugs. In this case, version number and skin info are necessary in order to reproduce your issue. Also, in the case of graphical anomalies, a screen shot would help.
I did a quick test of Masque r381 on the MoP beta using the Renaitre skins with Raven alpha r233 (built with Ace3 alpha r1051). I had to change one line in LibDualSpec (replace GetActiveTalentGroup with GetActiveSpecGroup) to make it work. I haven't seen any other issues, although it should be noted that Raven likely doesn't exercise Masque's full functionality.
I just finished updating Raven to use the Masque API. I removed all the skin save/restore code since Masque now provides that capability itself. I created a separate Masque Group for each Raven bar group which means that each can have its own skin now.
Would it be possible to add a Reskin method for an individual button? This would facilitate cleaning up Bartender4/Dominos buttons after Raven removes the highlight colors it optionally sets when buffs/debuffs are active.
A bug fix in the alpha r377 for Masque says: "Removed a reverse load dependency from Masque". Apparently, this interacts with how Raven specified an optional dependency only on ButtonFacade, which resulted in ButtonFacade not being found for some Raven users (reported by two different people but not replicated by me). In my latest build, Raven now specifies a dependency on both Masque and ButtonFacade, which seems to fix the issue. I mention this only for your information and in case other addons that specify the load dependency the same way as Raven did are affected. And, yes, I plan to update Raven to not use ButtonFacade backward compatibility soon.
I have a problem with using Masque in combination with Raven. If I pick a color on the skin I choose, it flashes grey for a second, and then goes back to white, and I have no idea why. I'm currently using Caith, but it's the same with other skins too
It sounds like you are trying to set icon border colors with Masque and having issues because Raven will, by default, color them itself. You can use Masque to color the borders if you go to Raven's Defaults tab, find the Masque options, make sure Enable is checked but disable both Color Normal Texture and Color Border Texture.
Alternatively, you can use Raven's icon border coloring options near the bottom of the bar group's Appearance tab. You can set a custom color there if you want. In this case, be sure that the Masque options on the Defaults tab have both Enable and Color Normal Texture checked.
I also recommend the addon ColorPickerPlus which lets you copy/paste colors in the color picker dialog so you can coordinate colors across bar groups.
Masque is not working with Bartender or Raven. No matter what I do, the skin remains the same.
Is there a previous version of ButtonFacade available?
Masque and Raven work fine in my testing (I am the author of Raven) and it also seems to work with Bartender on my system. Which skin are you using? I test with about ten skins currently. I will add your skin to my testing and let you know what I find out.
Please make sure you scroll down in Raven's Defaults tab to near the end and verify that "Color Normal Texture" is enabled and "Color Border Texture" is disabled in the Masque/Button Facade section. This is the default setting now and I hope to phase out "Color Border Texture" entirely once all skins are updated. "Color Normal Texture" works well with all updated skins tested (although border color is sometimes hard or even impossible to see with really dark skins but there is not much can be done in those cases and there are usually lighter variants available).