[Paint.NET 3.5.10 Lag]

I really dislike the new version and prefer 3.5.10

[Paint.NET 3.5.10 Lag]

Whenever I try to do anything the program lags at everything. What can I do to fix this?

[Best way to create the effect that part of an object in a picture was broken]

I'm creating a Sci-Fi picture and I have a character and want to make a metal-like article of clothing that sticks off the character look like it was broken in have by an explosion. If it helps here is the best definition of the substance I can give: Metal-like strength and durability with a feel of plastic 

[Changing colour]

(Not sure if this is the right Category. If it isn't...Sorry!)

 

I want to change all the Cream/White parts in this picture

http://s1293.photobucket.com/user/Christopher_Angell/media/Havoc_zps16596b76.png.html

(And the corresponding shades of cream or white) to a shade of Grey. The Hex is: 161616. I've tried to use Recolor but I get a different shade when I change to the shade of cream to one that is more grey. What should I do to rectify this problem and get the results I want