Jam hard on the red or white strip "ejector" device on the dagger so loosen it before extending it via the knob on the front of the daggerboard. Also I have wrapped my "dagger knob" in foam and electrical tape which helps get leverage, helps protect bare feet ( I don't wear booties) and also assists railing. Other sailors have developed even more extreme examples of these for additional leverage and incidental railing effect with some quite evil appearances of the enhanced appendage, reminiscent of scenes in Stanley Kubrick's Clockwork Orange.
In WA new boards are prepared by the retailer who inserts sail tape over the slot flusher gasket lips and this helps movement of the dagger and aids protection of the flaps.
If you want sail tape for the dagger contact SurfSail for advice and if suitable buy this product:
www.surfsailaustralia.com.au/product/Windsurfing/Windsurfer-LT/565797/Windsurfer-LT-Daggerboard-Flap-Dacron-Protective-Tape-Set-%282%29 Dacron Sticky Back Daggerboard Flap Protection Set (2) for Windsurfer LT - Protects daggerboard flaps from cracking - Makes daggerboard rotation smooth and easy - Price for 2 x strips black HD sticky back dacron - Each strip 900mm x 55mm .
Some use silicon lubricant to free up the dagger- I used to do this but this is not needed now if you follow all these instructions in my opinion. There are screws on the dagger case which can be loosened to make movement easier if required but you also don't want dagger to move too freely as it might slip while sailing- it's board tuning.
Also my centreboard case has been reversed. I understand the lightweight world champion does not do that, but many others do and it is better for operation and also in terms of position of dagger in case for efficient foil with better positioning.
For more information on this read this tuning guide and watch the videos which explains how to do it:
www.windsurferclassaus.com/setup--tuning-guides.htmlNick Bez (overall world champion 2019) does use silicon lubricant to loosen dagger, I believe but doesn't use dacron tape in the video. Lots of approaches work and some better than others and depending on how you attack the issue.
I hope this helps also good to ask local LT users in your area as well. Your retailer should help you too. Where are you ?