now, when i exclude everything from the package,except two doctypes, i get this error:

double post

Issue partly resolved, because i was only working in the backend (frontend doesn't exist yet) i didn't notice that i still had to run an updater script after overwriting the files with the new 4.5.1 version.

Some installation guidelines on this page could help prevent this: http://umbraco.codeplex.com/releases/view/48015

creating several small packages now worked, a big one with all my site content throws this error:

CreatedPackage.cs System.ArgumentException: 
No Document exists with Version '00000000-0000-0000-0000-000000000000'     
at umbraco.cms.businesslogic.web.Document.setupNode()     
at umbraco.cms.businesslogic.CMSNode..ctor(Int32 Id)     
at umbraco.cms.businesslogic.Content..ctor(Int32 id)     
at umbraco.cms.businesslogic.web.Document..ctor(Int32 id)     
at umbraco.cms.businesslogic.packager.CreatedPackage.Publish()

It appears i get this error because i select the top content node, when i select the first child i do get a package created.

now when i import this package i get this error:

Could not upload file
System.Exception: Error 
unpacking extension... ---> System.IndexOutOfRangeException: Index 
was outside the bounds of the array.
   at System.String.get_Chars(Int32 index)
   at umbraco.cms.businesslogic.packager.Installer.getFileName(String 
path, String fileName)
   at umbraco.cms.businesslogic.packager.Installer.LoadConfig(String 
tempDir)
   at umbraco.cms.businesslogic.packager.Installer.Import(String 
InputFile)
   --- End of inner exception stack trace ---
   at umbraco.cms.businesslogic.packager.Installer.Import(String 
InputFile)
   at 
umbraco.presentation.developer.packages.Installer.uploadFile(Object 
sender, EventArgs e)

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