Try VTi image, which is probably the best for Vu+ devices.
https://www.vuplus-support.org/wbb4/vtisoftware/
Clean OpenATV flash won't help you. Oscam has nothing to do with Enigma. In addition, you have to set everything up again from the newly installed OpenATV. Of course, you can try it if you want.
You can also try using the OpenMultiboot plugin (found on the OpenATV feed server - also in the Plugin MENU). You will then load the zipped firmware into the appropriate folder and flash it via the OpenMultiboot (plugin MENU). Then you just reboot and choose the desired image in the boot menu.