ESP32 GPIO 14 and 15

I have a working ESP32 (in particular the ETH01) that uses 5 digital pins to control some leds. In this particular package, the avaliable GPIOs are 2,4,12,14 and 15. I just bought another one and when flashing the latest relase (0.15.0) I cannot assing the GPIO 14 or 15 (among others, just that in this case those are the two that I care about). I tried both the Ethernet and "normal" versions. I know that this device can use those GPIO's and the ethernet connection and work just fine, as I have done it in the past and is still working just fine. The version that I installed in that moment was 0.15.0 beta 1. I would not mind reinstalling said beta version, as it seems to work just fine for my application, but I can't find it anymore.

Some help either on using those GPIOs or on finding said lost version would be apreciated.