This is mainly with focus on issues with the ECC code. One of these issues is a "possible overflow in ecc_ansi_x963_export" (https://github.com/libtom/libtomcrypt/issues/58). Other than that all changes are minimal, only one new compile flag had to be added to get around a compiler incompatibility case for LTC_FAST (we're not working with GNU compilers here) and the code will fully compile.
boost.signals sadly requires way too many dependencies, libsigc++ requires too much configuration and all the other libs I tested mostly required constexpr as callbacks (due to passing callbacks via template list), which doesn't server this purpose, so wink-signals seems just about right for what we do.