The "More Items Menu" drop down menu does clarify: "Manual Cycle: Wheel Over Button". I hope I have understood you correctly and that you will get used to this small adjustment.
Regarding artist images showing in album mode. Please note the following. Cycling of images for the current album only happens if "Sources > Cover" is set to cycle mode. If set to cycle from a folder then yes extra images are included. I set it to load the artist images by default because I like the ability to cycle through the cover and artist images, but you can use your own folder. You can also use foobar2000 sources for front, back, disc, etc, or both together. Set "Sources > Cover" to front to just have the front cover.
Track Gain adjusts the individual files to the same target volume on playback. Track and Album Gain are two separate scans. You can't (for example) select "Track" as the method for adjusting the volume if you've only run an Album Gain scan.
There's no reason why you can't keep the existing info, but I'd be using the ReplayGain right click menu to remove all the existing ReplayGain information, and then run a fresh Track Gain scan on all your files.
Is there any way where I could switch the way foobar controls the audio? So what I want is that all volume control in foobar, whether it's by keyboard shortcut or by volume slider or whatever it would be, would be controlling system volume, not the actuall foobar application volume. So if I have a volume slider in foobar, and I changed the system volume to 30% and then run foobar, I want it to show the slider third way through. If I then change it to 70% I want my system volume level to reflect that. Essentialy I want foobar application volume to be sticked to 100% at all times, and control system volume instead.
I'm running an old version of 1.3.8 of foobar btw.
Times change. I have created a tutorial in which I show how it is possible for everyone to publish high-quality sound (opus @ 160kbps) on YouTube.160kbps Opus may be perfectly adequate but it's not "high resolution".
And, are you sure YouTube won't transcode it? They may be transcoding everything, even if it doesn't need it... I don't know...
1) The correct way to handle this is to do the split in libopusenc. This will be gapless and glitchless. Everything else is going to be some kind of workaround that can still fail for pathological samples.
2) The signal in this file behaves badly in digital filters when they assume the signal before/after they operate is 0 (this is the default). To prevent this, you need to extend the signal, for example with a simple LPC predictor. Opus does this for the *end* of files, but not at the start. (https://github.com/xiph/libopusenc/blob/master/src/opusenc.c#L1147) I confirmed by mixing the Vorbis and Opus encodes that it's the start of the second file that glitches, not the end of the first one.
3) This needs to happen in both the resampler and the encoder. Easiest would be to have the resampler always do it, and feed the extended output to the encoder.
4) Vorbis implements it also for the start of files (https://github.com/xiph/vorbis/blob/ea8b03fce93444cb3cf0131909e15b4f8856e863/lib/block.c#L416) which is why it behaves so well here. (And obviously it can't fail at the resampling step).