Using the Park tool(junk) I had to improvise with PVC pipe and washers and the spindle bolt to hold the tool in place while tightening.
Maybe if you took the time to look around you would find that the Park Tool will work fine if you just know how to use it properly. Thin bladed fixed cup spanners need a clamp - period. Stein Tool makes a clamp specifically for holding fixed cup wrenches (it will even clamp an adjustable wrench):
see "Fixed-Cup Wrench Clamp"
Yes, you could probably make something that will substitute for the Stein tool, but I can tell you that the Stein tool works perfectly and I have used it with a BBT4 and it works great.
You badmouth the Park BBT4 ($8.50) when comparing it to a very nice TACX BB tool ($29.95). The Campy tool costs $67.50. As has often been pointed out in this forum, you usually get what you pay for. You tried to get off cheap and now all you want to do is complain. Even the very expensive Campy tool is going to work much better with the clamp. Any thin fixed cup spanner is going to work just fine with a clamp and will give you nothing but problems if you don't use one. At the high end of the fixed cup spanner spectrum are offerings from Hozan and VAR that will run you upwards of $200 and are appropriate if you wrench for a living or want the very best for tools.
Park, Pedros, Campy, VAR, Hozan, and Zog all make thin bladed fixed cup wrenches and all of these should be used with a clamp (~$40) or they will all be difficult to use. So, are all of these manufacturers making junk??? I don't think so. If you look in Barnetts at the list of tools suggested for "Fixed Cup Tightening", the tool at the very top of the list is the Stein FCC2 which I have referred to.
If you buy the clamp then you can buy all the cheap fixed cup spanners you want and they will all likely work just fine.
With all due respect, you are complaining about your own shortcomings - either as a mechanic or as to how much you want to spend to get the job done - and the specific tool you complain about has nothing to do with it. Would you cut steak with a butter knife? It would work, but there is a better and much easier way to do it.