Index: work/feature_poll/src/bus/long
===================================================================
--- work/feature_poll/src/bus/long	(revision 1614)
+++ work/feature_poll/src/bus/long	(revision 1615)
@@ -7,3 +7,5 @@
 process can be considered as drawing a very thick trace: as thick as the width
 of the "bus". The wide trace is just replaced with parallel traces the moment
 the user finalizes the line segment (or arc).
+<p>
+<i>Compatibilty:</i> not affected by a pure GUI feature
Index: work/feature_poll/src/fileform/long
===================================================================
--- work/feature_poll/src/fileform/long	(revision 1614)
+++ work/feature_poll/src/fileform/long	(revision 1615)
@@ -10,3 +10,8 @@
 NOTE: file formats do not solve the problems of internal representation of
 pcb data; thus it won't automatically bring blind/burried vias, better stackup
 handling, text-in-footprints, etc.
+<p>
+<i>Compatibilty:</i> not affected; the original pcb file format is kept, only
+the code is moved to a plugin; new file formats are obviously not loaded by
+mainline pcb.
+
Index: work/feature_poll/src/ppgrid/long
===================================================================
--- work/feature_poll/src/ppgrid/long	(revision 1614)
+++ work/feature_poll/src/ppgrid/long	(revision 1615)
@@ -3,4 +3,9 @@
 	<li> is a list of user defined grid sizes and origins
 	<li> is set and stored per project
 	<li> offers actions to changing grid up/down selecting the next/previous item on the array; so if the design wants 5, 10 and 25 mil grids, there'as a hotkey to switch "down" in 25->10->5.
-</ul>
\ No newline at end of file
+</ul>
+<p>
+<i>Compatibilty:</i> mainline pcb wouldn't understand this feature; a .pcb
+file saved with custom grid list embedde would make load error in mainline pcb
+(but the offending block is easy to remove with a text editor).
+