Rig tune?

That looks like a seriously out rig adjustment. Is the sidebend in the mast as severe as it looks in the pictures? I would go back to scratch and start again.
1/ Forestay length sets rake not rig tension so adjust to length to desired rake.
2/ slacken of D2 and D1 making a rough note of current rigging screw lengths.
3/ slacken of V,s Place an accurate tape wrap 2000mm apart on the non tensioned V,s Doesn't matter if you only mark 1 side but might as well do both.
4/ Start to tension up V's evenly on both sides. When firm measure from masthead to each side to ensure mast vertical. Adjust as required to get mast vertical. Once vertical tension rig by taking same no of turns up on each side. Do 2 turns aside until rig is firm.
5/ measure your tape gauge and tension to 2002 mm again evenly turning each side 1 or 2 turns a time.
6/ sight mast along ng trailing edge and tighten D1's to pull any curve out of lower section around spreader 1.
7/ repeat same D2's. Length of the rigging screws should say average the previous lengths or simply tension to what you feel is good.
8/ Sail with full main close hauled in about 12 knots. Observe leeward D's to see if they are slack.
7/ Tighten D's as appropriate and repeat sailing in slightly stronger breeze until satisfied.
if the leeward shroud becomes slack during this process you could try up to 2002.5 mm tension but will depend on how stiff your hull is.

I second the idea of downloading the Seldon Rig PDF very informative, they advise swept back 9/10th rigs should be carefully set. I used a 2 metre rule, as per Selden advised, but I guess Frants method is much the same. What are you doing with the main, it looks like the headboard is going to foul the back stay?
ive got the same style of SElden rig, but my cap stays are 10mm up to the bottom spreader, then 8mm thereafter.

Cheers Richard