Transport Layer Security (TLS) to allow more secure communications across the network and used by the more modern gnutella programs. Using this will tend to invite the likes of Lime-code based apps, GTK-Gnutella and Phex but exclude the older apps. I don't know much more.

The earliest Lime code based implementations of TLS often had a side effect of causing problematic connecting to the network (possibly due to the TLS software implementation not being universally compatible with all hardware routers.) Both Cabos and Acqlite even had TLS disabled by default. But it was improved by the release of LimeWire 4.18 (of which the Cabos & Acqlite dev forgot to implement despite his last update around the same time.)

WireShare 5.6.6 is fine to update to. You will no doubt also better benefit from the hostiles updater it provides which was added for this version and by the gradual removal of out-of-date data (which also applies to WireShare) will help provide more hosts to connect to and share files with. Hostile updates are done silently, at start of a session when any updates exist. This version also utilizes GWebCache to help find fresh hosts to connect to.
I don't personally agree with some of the changes (removals) to the Adult filter (WireShare 5.6.4) that over-rided a small part of my work of a few years ago. But I guess ignoring years of real-time research is irrelevant and decisions based on whims is much more than fine.