(pak64, Win-GDI+SDL)
It seems that a long-block-signal will cause a blocked train if the p****ing train has to stop at the tile directly after the signal. At a simple signal, this doesn't happen.
See savegame: the train (line01) is already stuck; you can sell it immediately, then start the other train (line02) in the depot, which will also get stuck. Use 'b' to see the reservations. The savegame doesn't load in 99.17.1, so I couldn't test there.
BTW: I cannot upload .SVE, I first have to put it into .zip, although it is already zipped, and very small (20kB).
Should be fixed in r1953; sve should be also legal attachment.
With R1950 and Pak128 I found that it's even not possible to place a long-blocksignal.
That's a bug in Pak128 rev. 61 (my fault, I tested the wrong files after changing the signals' dat file). It's
supposed to be fixed in rev. 62.
EDIT: original bug fixed in rev.1953 => closed.
Checked in r1953. Solved!