IndexOutOfBoundsException / NoSuchElementException with rounded corner directly next to box

[Flupp]

The following pictures result in exceptions:

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results in

ditaa version 0.11, Copyright (C) 2004--2017  Efstathios (Stathis) Sideris

Running with options:
Reading file: mapdb.ditaa.txt
Exception in thread "main" java.util.NoSuchElementException
        at java.util.HashMap$HashIterator.nextNode(HashMap.java:1447)
        at java.util.HashMap$KeyIterator.next(HashMap.java:1469)
        at org.stathissideris.ascii2image.text.CellSet.getFirst(CellSet.java:81)
        at org.stathissideris.ascii2image.graphics.CompositeDiagramShape.createOpenFromBoundaryCells(CompositeDiagramShape.java:84)
        at org.stathissideris.ascii2image.graphics.Diagram.<init>(Diagram.java:366)
        at org.stathissideris.ascii2image.core.CommandLineConverter.main(CommandLineConverter.java:252)
return value 1

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results in

ditaa version 0.11, Copyright (C) 2004--2017  Efstathios (Stathis) Sideris

Running with options:
Reading file: mapdb.ditaa.txt
Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 1, Size: 1
        at java.util.ArrayList.rangeCheck(ArrayList.java:659)
        at java.util.ArrayList.get(ArrayList.java:435)
        at org.stathissideris.ascii2image.graphics.DiagramShape.connectEndsToAnchors(DiagramShape.java:688)
        at org.stathissideris.ascii2image.graphics.CompositeDiagramShape.connectEndsToAnchors(CompositeDiagramShape.java:217)
        at org.stathissideris.ascii2image.graphics.Diagram.<init>(Diagram.java:372)
        at org.stathissideris.ascii2image.core.CommandLineConverter.main(CommandLineConverter.java:252)
return value 1

I used version 0.11.0-3 on Arch Linux.

#37 might be related.