Hello, to break the blue crystal barrier you need to perform a perfect strike, for which you need to release the attack button right after the cyan flash and sound indicator. It's a timing thing.
Those gates are there to teach this mechanic, as it is very useful and important in combat.
The "for older pcs" game version does not work on Windows 11 due to an engine issue or an issue of the OC itself. So far there is no way to fix this, so I recommend sticking to the main Vulkan version.