I'm playing through the the game before TW2 gets release (I know I won't finish before that happens) and I I can't for the life of me figure out how to get runes crafted onto my silver sword.

I do have a rune in my inventory that specifically say that it can be inscribed on a silver sword but when I go to the dwarven smith in Vizimia, the only thing I can do is sell the rune to him.

On a side note, Siegfried also disappeared before I could submit a completed contract to him. I've wandered by his room at all different hours with him not there. The only thing I can think of was he somehow got scripted out when I ransacked everyting out of his room to sell.

Thanks, I did a bit more hunting around in the Witcher wiki and found my other answer about siegfried.

So what was the problem with Sigfried?

From what I remember, three red meteorites are best for iron sword

Good rune combinations are:
sun, earth, earth
moon, moon, earth

Have similiar problem i have it but still i can only enter the "shop"

If you're in Act II, there are two armorers, but their disposition depends on actions you've taken so far. You can get yourself in a situation where both hate you.

The Order armorer, who stands in front of his shop, won't deal with you if you turned Siegfried away and fought the cockatrice on your own, or if you cleared Golan Vivaldi of collaborating with Salamandra. If he won't deal with you, you have to do something in favor of the Order (side with the Order in "Force Recon").

The Dwarven blacksmith, who is in his shop in the Nonhuman District, won't deal with you if you killed the Scoia'tael outside Haren Brogg's house in Act I. If he won't deal with you, you have to do something in favor of the nonhumans (clear Vivaldi, rescue the half-elf woman, or side with the Scoia'tael in "Force Recon").

Siegfried (in the 2nd chapter) goes to the swamp. You can find him and his men near the druid's camp - they preparing for a battle against the squrells. By the way, in the squirell camp the elves are preparing, too. You should choose (it's not necsesary) a side, and you have to fight the other one.
Depending on your choose, the dwarven smith or the order armorer stops dealing with you (if you choose the order, the dwarf stops, and vica versa), until you do the next faction choose.

After you complete the mission (or start chapter 3), siegfried returns.

I still do not know how to improve the sword. NPC talks to me, but when I click the icon for improvement, Im received the shop menu.

What you see is correct (though I'm not sure what the dagger is doing there).

When you select the "forge" icon, you get a menu with all the swords that can be forged. The Red Meteorite sword is in that menu; you can see it in the second picture. All you have to do is buy it.

I sold it earlier. I exspected something like crafting window, well... Thx for help

It's kinda a carfting window... A little bit. You can see all the items the vendor can sell to you and all the sword you can make from the stones in your inventory. So, if you have 3 stones from every type, you can choose from 9 swords. Hoover your mouse on the swords to see the description for it - you will see the stats and what stones it made from. After you chosed what you need the used 3 stones are disappear (smelt into the sword), and you have an another sword (so, if you had 1 sword, now you have 2).
This is working for silver swords, too, but there you upgrade your original sword, and not receive an other.