I am using a Windows 10 PC together with a JRE 1.8 and matching JavaFX version. I am currently dependent on this Java version. When I run Cryptomator 1.6.17 on this PC (as executable file) the GUI does not start. Is there any way to get the Cryptomator version to use only the files it brings itself and ignore the existing Java/JavaFX installation?
Welcome to the Cryptomator Community, 
this issue will be fixed in the next patch release, see also Windows: GUI not displayed · Issue #2814 · cryptomator/cryptomator · GitHub.
Version 1.7.4 alpha1 opens the GUI now. So the conflict with the existing JavaFX seems to be fixed. Nevertheless it is not possible to access encrypted data on one drive.
Please update to version 1.7.5 as soon as possible due to a bug in the filesystem implementation.
Without additional information what and after which steps it fails, no one can help you. If an error screen is displayed, you can search the error code in our error database.