I can confirm that this solves RC issue.
As for Spider Gate, I assume kernel is not the problem ?
The problem is missing required kernel modules.
Please be sure to have all options marked with '+' sign from attached diff in your kernel.
With this options enables I was able to run Spider Gate. If this wouldn't help you - provide your kernel config.
Regarding RC - we don't officially support Gentoo distribution - so we have missed breaking changes in OpenRC. We will try to fix it in upcoming release.