Issue with upscaled icon-sheet

[Troller0001]

So stupid me didn't read enough and thought that for promotion icons you only need a 64, 45 and 32px-version. (Turns out you also need a 256*256px version).

Anyhow, so I thought that re-sizing the 64px icon sheet would make a great 256px icon sheet (a bit blurry, but I didn't feel like re-creating the icons). However, for some reason, Modbuddy doesn't like the upscaled version...
Whenever I add the 256px icon sheet (resized from the 64px icon sheet) and try to build the solution, I get this error inside Modbuddy itself (NOT In-game):

C:\Program Files (x86)\MSBuild\Firaxis\ModBuddy\Civ5Mod.targets(129,9): error MSB4018: The "PackageMod" task failed unexpectedly.
SevenZip.SevenZipException: The execution has failed due to the bug in the SevenZipSharp.
Please report about it to http://sevenzipsharp.codeplex.com/WorkItem/List.aspx, post the release number and attach the archive.
at SevenZip.SevenZipBase.ThrowException(SevenZipBase handler, Exception[] e)
at SevenZip.SevenZipBase.CheckedExecute(Int32 hresult, String message, SevenZipBase handler)
at SevenZip.SevenZipCompressor.CompressFilesEncrypted(Stream archiveStream, Int32 commonRootLength, String password, String[] fileFullNames)
at SevenZip.SevenZipCompressor.CompressFilesEncrypted(String archiveName, Int32 commonRootLength, String password, String[] fileFullNames)
at SevenZip.SevenZipCompressor.CompressFiles(String archiveName, String[] fileFullNames)
at Firaxis.ModBuddy.Civ5ModBuildTasks.PackageMod.Execute()
at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()
at Microsoft.Build.BackEnd.TaskBuilder.<ExecuteInstantiatedTask>d__20.MoveNext()
========== Build: 0 succeeded or up-to-date, 1 failed, 0 skipped ==========

The 32px and 45px icon sheets (also resized from the 64px icon sheet) are working perfectly fine and don't throw this error, but for some reason the 256px icon sheet does throw an error when I try to Build the Solution... Anyone knows why?


EDIT:
NOTE: I don't even have 7zip installed if that's what the error is referring to....
I used these settings when converting to a .dds

RGBA8 encoding
No Mipmaps
No compression

 

[Troller0001]

For some reason, after spam-clicking the rebuild-button at least 50 times, checking if I there was anything within Modbuddy's properties, and then waiting for 15 minutes allowed the solution to be built... What the actual

To close this thread I would like to use a quote by Whoward:

"Weird" is Firaxis' middle name (along with "pointless", "inconsistent", ...)