Hi,
While the differences between the 0.5 and 0.62 are minor (to me at least), they are enough to break backwards compatibility. It came down to a lot of element/attribute name changes, along with some namespace changes as well. Also, the inclusion of the baseType property allowed me to rework things so that they were a tad bit more efficient.
As you alluded to, the most recent version of CMIS Explorer will only support the 0.62 specification. However, you should be able to use the 0.4 version of CMIS Explorer with EA2.
Shane