Hi biancoluke,
Welcome to the forum.
Excel is a bit restricted when it comes to editing images, I did however find something you might want to try out.
If you download and install a free program called 'ImageMagick' (easy to find on Google) we can use a command line instruction to collate the seperate still GIF's into one animated GIF
See code below:
Sub AnimateGIF()
Dim sPath As String, sCMD As String, sPRMs As String
Dim sFiles As String, sTarget As String, sRunString As String
Dim ConvertLoc As String, FrameDelay As Integer, GIFoutName As String
Dim WshShell As Object
sPath = "C:\Users\jbloggs\Desktop\test" ' < Folder where still GIF's to be converted reside
ConvertLoc = "C:\Program Files\ImageMagick-7.1.0-Q16-HDRI" ' < Install folder of ImageMagic
FrameDelay = 50 ' < Delay you want between frames of the GIF
GIFoutName = "CompletedGIF.gif" ' < Output GIF file name
sCMD = """" & ConvertLoc & "\convert"" "
sPRMs = "-delay " & FrameDelay & " -loop 0 "
sFiles = sPath & "\*.gif "
sTarget = sPath & "\" & GIFoutName
sRunString = sCMD & sPRMs & sFiles & sTarget
Set WshShell = CreateObject("WScript.Shell")
WshShell.Run sRunString, 1
Set WshShell = Nothing
MsgBox "File: " & vbNewLine & sPath & "\" & GIFoutName & vbNewLine & "Was created"
End Sub
It will place tha animated GIF in the same location as the stills.
I did try to reference the dll file for the above program but it did not go well so i went with command line.
Hope this helps