The shareware distributions are actually full games (which had been purely commercial titles prior to the 2001 release), and anyone downloading them is licensed to play freely for the 30-day evaluation period, after which the game should either be registered or deleted:
The license file included with both games further states thatWe have now released Frontier and First Encounters as shareware. There is a £5 registration fee which applies if you continue to play either game for more than 30 days. We strongly recommend reading the readme.txt file included with each game before playing.
which I guess means that both can be added to the site, provided the relevant shareware information is indicated exclicitly.You may without making any payment to AUTHOR make copies of the evaluation SOFTWARE as
you wish; give exact copies of the original evaluation SOFTWARE to anyone; and distribute the
evaluation SOFTWARE in its unmodified form via electronic means (either directly or through the
posting of a copy of the SOFTWARE on the Internet, BBS's, Shareware distribution libraries, CD-
ROMs, etc.) to third parties who are interested in evaluating the SOFTWARE except for the
purpose of extending their evaluation period
The games are no longer available from the Elite Club website, however no legal statement that would void quoted license had been issued either (to the best of my knowledge that is). The shareware files can be either obtained at the archived copy I have linked to above, or at the FrontierAstro website.