From the look of the smoke it is evident that the gasifier is suffering from fuel with too high a moisture content and too dense (not enough air spaces).
I expect you will get much better results with screened (classified) wood chips, and especially if they are well dried.
I also agree with Kristijan, Steve and others that the system design is fundamentally flawed. As suggested, it can be made to run far better by converting somewhat to an Imbert design. The equipment is certainly capable. For a properly running system the multiple cyclones etc shouldn’t even be needed.
To experiment and prove operation first you need properly sized, low moisture wood chips. And preferably dry charcoal in the lower part of the gasifier to start out.
There is a member of DOW from South Africa who ran a sawmill for many years on mill waste successfully, so your stationary application can certainly be achieved with the right size fuel, right moisture content, and right operator intuition/ experience.