When a number is large enough to include thousands separators(I.E. 10,000 and up), the speech engine will not match it to a command(it does "recognize" it, as the number appears in the log correctly).
I'm assuming this occurs on machines with regional settings that use "." as the thousands separator, because the speech engine will use "," instead(For English US/UK at least), which is probably why this hasn't been encountered before.
This can be worked around when manually entering command phrases by inserting the separator beforehand(E.G. "Travel 400,000 light seconds".
However, when interpolating numbers using dynamic command sections with numeric ranges(E.G. "Travel [1..400,1000] light seconds") the automatic addition of spaces between sections does not allow a workaround(E.G. "Travel [1..9,1000] light seconds;Travel [10..400],000 light seconds").
This does appear to be a speech engine issue, as a manually entered number without a separator(E.G. "Travel 400000 light seconds") isn't matched either(I.E. even if the numeric range does not generate thousands separators, it still wouldn't/doesn't work).
EDIT: Still applies to v1.7.3
EDIT#2: Also applies to v1.7.3.1
EDIT#3: Also applies to v1.7.3.9
EDIT#4: Also applies to v1.7.5.8
EDIT#5: Fixed in v1.8.3.22