The 45 is a very simple stove - it runs on Kerosene NOT COLEMAN FUEL.
Lights OK but the flame dies away without continuous pumping - pressure leak either from the filler cap or from a dead NRV, if its the NRV the pump rod slowly extends...
Burner keeps blocking -> cr@p in the burner head - blowtorch and bucket time (yes you will want the double jointed spanner thing).
Fuel leaks from base of the burner - you forgot to tighten it up.
Yellow-orange flame (it ought to be blue) -> over-sized or damaged jet -> replace.
Even when they work, they don't work well. I blame engineers.
The only thing engineers have done to the toaster in the last 80 years is make it disposable. I think it applies to a lot of things