I have been working around a bug for the past several versions of Hog 4 OS related to a IPCB fader and BPM changes. Please note that I am unaware if this has ever worked as I only started using this particular workflow in the past 8 months.
TL;DR: IPCB Crossfade bugs to 100% if you change the BPM of a cue only cuelist and then try to cross fade into a cue on the cuelist.
In my workflow, I build a cuelist or two of effects for fixtures (Intensity Invert Ramps, Pan/Title Circles, etc) and set the cuelist to be Cue Only where each individual cue is its own effect. I set these effect cuelists to IPCB Crossfade in Standard Master mode so I can fade in the effect while having some control of the rate and size of the effect (I know the rate and size can be controlled via dedicated masters in the different master modes but IPCB Crossfade works while limiting fader usage). The problem is when I need to change the BPM associated with the playback master. I typically use the BPM tap feature on the playback to change to the BPM I need. Once the BPM is changed and the fader is increased (from zero) to any percentage value, the resulting output jumps to 100%. However, when you set the fader to 100% (while it's already bugged to 100%) and then bring the fader back to 0%, the expected behavior (IPCB crossfading) applies when you move the fader up to any value).
The current workaround I have is to crossfade on a "Reset" cue (null cue) after changing my BPM on the playback master. This gets the bug out of the way and allows me to crossfade on another cue in the cuelist without having the distracting bump to 100% when I only meant to crossfade to 10% instead.