I am sorry, but once you are at BIOS 367, you simply cannot downgrade. This is because changes were made in the Management Engine firmware in BIOS 367 to mitigate the INTEL-SA-00086 security vulnerabilities (for more information, see here: INTEL-SA-00086 Advisory). Now, once a security update is made to the Management Engine firmware, it will not allow downgrades to any previous version. This is a design feature of the Management Engine that simply cannot be circumvented. I am sorry, but you will just have to wait for a new BIOS update to be made available.
The BIOS was withdrawn because of instabilities in the microcode updates made for the SpectreB vulnerability (for more information, see here: Facts about The New Security Research Findings and Intel Products and here: INTEL-SA-00088 Advisory). Unfortunately, this instability manifested worst in the microcode for the Haswell (4th generation Core) and Broadwell (5th generation Core) processors. You have already encountered and described it's instabilities fairly well.
Since the BIOS withdrawal was done, Intel has root-caused the microcode issue, made the appropriate changes to the various microcode releases and is in the process of validating these changes. Once the validation is complete (and presuming it is satisfactory), the microcode will be released to board manufacturers. They, in turn, will be responsible for including the appropriate microcode releases into their product BIOSs and releasing them to their customers. Intel's NUC team will be similarly responsible for doing this for the NUC products and also for the older Intel Desktop Board products. They will publish their schedules for delivery of the various BIOS updates to these locations:
Unfortunately, these schedules cannot be set until the microcode is made available (that's why they are blank right now). All I can say is, watch these sites for schedule updates.
I wish I had a better answer, but it is what it is. Don't shoot the messenger; I am retired and a volunteer here.