Hi, for the task you are describing there is very powerful tool which is part of Forest Pack Pro : Forest Tools
which allows you export your scattered geometry as instances. You can find it under Utilities panel - More ... - Forest Tools. Please check the reference link. You have a lot of possibilities what will happen with your instances after conversion to mesh (for example moving all instances to new layer is very useful).
In case you are already using Forest Tools is there any error message during conversion process?
Please let us know if it works for you now. Thanks in advance.