I am still using Rephase to build the crossovers, and the combination of Room EQ Wizard and DRCdesigner.
I have moved away from Foobar to Logitech Media Server using the local player plugin. This allows me to integrate Tidal with a remote, and make use of the sox resampler built into local player.
Local player outputs to Reapers Asio driver without issue.
I still use reaper to process the audio and run the crossovers with some minor differences. I am now using Reaverb, the built in convolution engine to run the FIR crossover filters and DRC correction filters. I also found that setting the volume levels for the individual drivers in Reaverb works better than using the setting in the I/O panel, as the level meters are not affected by the setting in the I/O panel, meaning you could potentially be clipping without the meter displaying it.