Here is my understanding of your problem:
Say your orginal version number of the graph is "100" and after you made the first set of modification and checked in, the graph gets a version of, say "102".
Now you checked out the latest version of the graph, i.e. version 102 and did another set of modifications. After checking in (say new version number 105) you realise that the changes were incorrect.
In such a case the correct version is 102 on which you have to make the second set of changes again.
To achieve this, check out version 102 (select appropriate version number in check-out wizard), check it in again without any modification and setting the "force overwrite" option on. This will create a new version of the graph, say 108, and this version will be the same as version 102.
So now you have version 102 as the latest version with a new version number 108, you can lock and make the correct modifications on it.
Another way is to branch out, but in your scenario it doesn't appear to be the right option.
I have used version numbers in the explanation, which can be replaced by "tag names".

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After you realise that your chage is wrong, press unlock button, save the changes in other file name. Checkout again the same graph with correct version.
Best practice
1. Checkout all the graphs from a project to the corresponding sandbox
2. Checkin only the changed graph.
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You can acheive this by using the concept of tags in abinitio. You check out a graph with tag name later when you don't want the modifications and you wish to revert back to the original version you can acheive this.
Hope this helps,
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According to your problem statement, all the 10 graphs that you checked in into the EME get stored there as the latest graphs with the latest tag. This thing also reflects inyour current latest sandbox.As you checked out and modified the graph by locking it in your own sandbox, and found that the modifications were not correct, you can simply follow this simple approach. Dont checking anything into the EME. Just re-checkout the graph from the EME (which is actually unaffected by your modifications) over the modified graph in your sandbox. This will sort of overwrite the unmodified graph (which you want) over the unwanted modified graph. This solves your problem.
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Check out the previous version of the graph from EME to sandbox
Abhisek B
fresh as dew!!
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The above answers stays valid if you did not checked in again after making the modifications. As the modifications are saved in sandbox there is always a revert back option by checkout to the previous version of the graph from EME to sandbox.
Abhisek B
fresh as dew!!
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I agreed to above explanations. However if I didnt used a TAG while checking in the version which I want to checkout later on then well in that case what we can do? Any suggestions?
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Yes you can check out the older tagged version. As far as I know EME has untagged versions also.
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mikhail
Answered On : Dec 13th, 2011
Could we check out using the version number?
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AKG
Answered On : Feb 6th, 2012
Check Out from older version which is the correct one and check it in again. Make sure of using correct version number while checking out.
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ruchi
Answered On : Nov 6th, 2012
Just unlock the graphs!
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Srinivas
Answered On : Nov 22nd, 2012
If you are not tagged the older version object (102).. and still you want to checkout the older version, than create a tag for the older version (102) by using r-tag option and do a checkout.
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