I tried to enable the personal and world anchors by changing their booleans in railcraft.cfg. However they aren't showing up in JEI and I can't do the crafting recipe (I have a separate server/client). I checked the server log and I see:

[18:29:31] [Server thread/INFO] [railcraft]: Module performing stage PRE_INIT: railcraft:chunk_loading +
[18:29:31] [Server thread/INFO] [railcraft]: Entity{cart_anchor_world} cannot be defined because Block{machine_alpha} is disabled
[18:29:31] [Server thread/INFO] [railcraft]: Entity{cart_anchor_admin} cannot be defined because Block{machine_alpha} is disabled
[18:29:31] [Server thread/INFO] [railcraft]: Entity{cart_anchor_personal} cannot be defined because Block{machine_alpha} is disabled

However this is not true, the mentioned block is are enabled in blocks.cfg (as is the default):

B:machine_alpha=true

Then how do I enable the anchor blocks?

Railcraft version: Railcraft_1.10.2-10.0.1.jar
Direwolf20-1.10 modpack version 1.2.2.

See #1010. @Forecaster

As of now you can not as most of that modal has not yet been ported over.