Lots of CIS systems had hot start issues. Many manufacturers had fixes that worked around the cold start valve. I do believe VW used this trick too.
If you elect to purchase it, I would check the pressures and get them set up to stock. Set the main pressure, then the hot control pressure, and finally the cold pressure. In that order. You can probably play with the cold pressure to suit your area. I would check the distribution from the fuel distributor. Make certain they all flow the same amount. There are some adjustments so all the injectors flow the same. Most of these adjustments are not in any Bentley since they are not approved.
Once everything is set up properly, you will probably find your problem gone. The fuel accumulator can cause issues but I've never really seen it help a hot start problem. Leaking fuel injectors can cause a hot start problem.
If you have any problems with the CIS components, good luck with finding any good stuff. CIS systems like good fuel and although the vehicle has 50k, that may not be ideal for that fuel system. Condensation in the fuel tank, varnish, rust, etc can really cause havoc to a good fuel system. Especially rust.
Manufacturers do not use copper lines for brake lines and I hope you do not do that either. It's dangerous.