The microscopic sample of water trapped in a tiny sample
from the Lunar regolith brought back by the Apollo 15 crew
indicates that water molecules may be or was trapped in Lunar magma
at average proportions of 260ppm.

How practical is it to access that water for Lunar colonization?

At 260 ppm, the 'average' amount of water in 5,000 tons of Lunar magma would
work out to about 260 pounds....Hardly seems worthwhile to extract it.

But....Is there a possibility that water, by means of osmosis, may have been
concentrated in certain deep layers/strata of hardened Lunar magma shortly
after the moon's surface cooled?