Auto transition vbscript time stamp

Looks like you are fairly close.
I would use this line to check the result of your DateDsz calculation (insert it temporarily just after the calculation)

err.raise MFScriptCancel, DateDsz

From the looks of it you may get negative results. If so you can switch the order of Date,szDate, or you can adjust the next lines to work with the negative result.

You should also have a look on this line:
If  DateDsz = 24 or  Then

You need to remove OR, and you should use DateDsz >= 24 to allow for situations where more than 24 hours may have passed.

I followed your suggestion for the error.  i adjusted the Order to DateDsz = DateDiff("h",Date,szDate)

and got an error of -13 and if put the same i got error 13.

I edited my script like this now to test if with minutes. But it's not transitioning after 2 minutes or so.

Option explicit
Dim PropertyValues : Set PropertyValues = Vault.ObjectPropertyOperations.GetProperties(ObjVer)
Dim oObjId : Set oObjId = CreateObject("MFilesAPI.ObjID")
Dim classID, szTime, TimeDsz
classID = PropertyValues.SearchForProperty(100).TypedValue.GetValueAsLookup().Item
szTime = CDate(PropertyValues.SearchForProperty(20).TypedValue.DisplayValue)
TimeDsz = DateDiff("n",Date,szTime)
If classID = 41 or classID = 42 or classID = 202 Then
If TimeDsz = 2 Then
AllowStateTransition = True
End if
End if

The "error" should be the result of your calculation.
If that looks correct, your calculation is in order. Then you just have to wait until 24 hours have passed.
Changing to Minutes will not make much of a difference anyway. The server is only checking once per hour (default setting), so the transition will happen some time within an hour after your "IF" becomes true.

The error means the result of the calculation? I've tested it if the object was created at 2pm the erorr says 14. so it means 1400h? I also change the sequence from Date,szDate to szDate the result was -14.

So the non negative result means the correct one?

If you are still taking about the error that came as a result of err.raise MFScriptCancel, DateDsz then yes. The test shows the outputvalue of DateDsz in this case. You can use to test any part of your script as long as you place after the calculation of the variable that you place in the last bit of the string.

DateDiff calculates the difference - not a new timestamp. 14 or -14 is the difference between Date and szDate measured in hours in this case. It is 14 hours, not a timestamp for 14:00.

Sorry for many questions. But the Created Time is actually 2:00PM then current time is also 2pm. But the result is 14 and -14 if switch the 2 properties.

So my Datediff is incorrect? It should be 0? 

I change the "Date" to Now(). the result is now 0.

Is this the correct variable?

Sounds right. Date will just give you the date. Now() will give you the time as well.