Key-presses happening multiple times during OpenBSD installation

I am trying to install OpenBSD on HP Chromebook 11 G4 with CoreBoot (UEFI) installed through MrChromeBox firmware-util script. During the initial boot prompt (when you see the boot>) I can easily type anything there (like entering into User Kernel Config with boot -c for example). But after loading the installation program each time I press any key, and I mean literally any key including power button or enter, I need to wait for 1-2 seconds before chromebook responds. What is even worse is that each key-press is recorded/recognized multiple times. I have already found that setting kern.timecounter.hardware=acpihpet0 using sysctl can help but unfortunately I can't get past installation (typing "done" is not an option and it is required in some places because of failed load of initial iwm0 firmware) I know it might be the tip of an iceberg but I would like to begin with fixing the key-presses issue during an installation process. Since this suppose to be a question there should be at least one question mark. Is there any way to set kern.timecounter.hardware=acpihpet0 from UKC or any other way to fix each key being pressed multiple times during installation ? As a side note: from I can see most things during boot are not configured (like acpicpu at acpi0 not configured or Intel Bay Trail LPC .... not configured. Oh and I have already tried using an external keyboard with no luck since it does not work during installation program for some reason. Update: Just to preempt question since I did not mention this in the original question. The installation program does not detect any disk except for the build-in emmc. If it was not for this I could simply install the OpenBSD with autoinstall (multiple "a" count as 1 in that particular prompt and naming the response file like "bbbbb" works). Because of the above and the fact there is only wireless connection build-in I can't get sets necessary to finish the installation. I've managed to get past disk layout stage but there is nowhere I can get the sets from since the installation medium is also unavailable. Update 2: I have managed to install OpenBSD via Linux MX live usb with virtualbox installed. Sadly the keyboard is still not working. Any external usb device is not recognized either. When I press the power button I can see there is an info with something like:

pckbc timeout

I will keep this question updated.