@fery, @dl45, thanks for sharing your results with TPU. I've been doing some investigation before attempting flexible filaments myself.
Angus from Maker's Muse goes over some guidelines when using flexible filaments.
a) For the layer adhesion issue, have you tried slightly higher nozzle temperatures? 220⁰C might be worth a shot. (See Maker's Muse - Tip #6 - Increase Print Temperature)
b) For the stringing issue with the flexible filament, have you tried settings in your slicer to avoid those crossing paths? I think in the latest CURA there is a similar feature under Travel settings (see Cura - Combining & Maker's Muse - Tip #7 - Avoid Crossing Outlines)
Finally, and perhaps not applicable to flexible filaments but stringing in general, there is yet another video from Maker's Muse regarding how to tweak the slicing settings in CURA to reduce stringing in an Ender 3. This should apply to the CR-6 as well. (see Maker's Muse - Stop Ender 3 Stringing)
Regards,
-R