MixSilmeria

You can do them with any image editing program (photoshop, illustrator, inkscape, paint?). You should try different sizes and see the results, the size of the icons provided (512x512) is ridiculously giant TBH, maybe you should try 128x128 or 256x256 and see how it looks. Smaller sizes should load faster, but maybe the visual quality gets worse (if it's vectorial you shouldn't have problems, I suppose).

Test without fear, I'm glad that the skin is useful for you
Cheers.

Hi fabio, yes, I think you can, but I don't remember how. Maybe there is something like "wait(time)"? you'll have to read the official documentation. I'm still using my skins but I have not written any "code" of Rainmeter since I uploaded them, sorry for not being able to help you more ):

And for your other question (about the gif of how to invert the colors to make the icons), here you go

We only search "{something} metro icon", and if it doesn't exist, you can made your own icons (I use photoshop, but Illustrator and Inkscape are nice too, the last one is free btw).

Yes, totally. Take a look at my other skin (Just A Bin). I think if you copy most of the code and do some tweaks you'll get what you want.

Hi Jo, I really appreciate your words, please try this (change the lines with -->):

[MeterActionZone]
Meter=Image
X=0
Y=0
W(#TotalIcons# * (#SpaceIcons# + #IconSize#)) - #SpaceIcons# + 20)
--> H=#LineThickness#
SolidColor=0,0,0,1
--> MouseOverAction=[!CommandMeasure MeasureFade "Stop 2"][!SetOption MeterActionZone H "(#IconSize# + #SpaceLineIcons# + #LineThickness# +10)"][!CommandMeasure MeasureFade "Execute 1"][!UpdateMeter MeterActionZone]
--> MouseLeaveAction=[!CommandMeasure MeasureFade "Stop 1"][!SetOption MeterActionZone H "(#LineThickness#)"][!CommandMeasure MeasureFade "Execute 2"][!UpdateMeter MeterActionZone]
DynamicVariables=1

Damn deviantart and this hashtaghs thing...I can't try it now but I think it should work

And if someone else reads this. If you make something great using my skin as base, upload it, share it with everyone. I'll not make more changes for this skin anymore. So, if you improved my skin, please upload your new version (and let me know so I update my setup!! ahaha)
Cheers! (: