From FreeSpace Wiki
Those continuation flaws that occur regarding jump nodes between FreeSpace: The Great War and FreeSpace 2 are called node inconsistencies.
There are a number of jump node connections that are used in FreeSpace but are not illustrated on the Official Volition Node Map. They are listed below, along with their references and how valid you should consider them. Volition says that the node map should overrule other references.
These connections are used in-game and would be considered canon if it weren't for the official map.
Used in First Strike (SM1-10). Admiral Wolf says that the Taranis has been chased from the Beta Cygni system back to the Ikeya system, and the Taranis is fleeing to the Beta Cygni node during the mission itself. It is very likely, however, that this is a mistake. The cutscene immediately preceding this mission (not to mention the official node map itself) shows that the only subspace node out of Ikeya leads to Ribos. Additionally, during the mission, Freighter Halkins tows the cruiser to Tombaugh Installation, which is located in Ribos. It is probable that the mission designer just confused Ribos with Beta Cygni.
Used by the player's squadron and Omega wing. The node is seen in Reaching the Zenith (SM3-04) and used in Running the Gauntlet (SM3-05) and Black Omega (SM3-06). Xenolinguists are transported to Altair to retrieve the ancient records and back to Deneb to rejoin the Terran fleet.
Command Briefing Animation
These connections are shown in the animations that accompany the FS1 command briefings.
Seen in CB_starmap06 and in CB_starmap08
Seen in CB_starmap06, although Betelgeuse isn't labeled. However, considering that the Command Briefing cutscene locates Ikeya where Betelgeuse should be, it is possible that this cbani is meant to refer to the Ribos-Ikeya node.
Seen in CB_starmap08, although the jump line isn't explicitly drawn
Seen in CB_starmap08
Seen in CB_starmap04, although the jump line isn't explicitly drawn
Is seen in La Ruota della Fortuna (SM2-03), showing ships being attacked in Vega and subsequently jumping to Deneb and Antares. Admiral Wolf says that the Vasudan fleet is retreating after having been decimated by the Hammer of Light.
Is seen in Tenderizer (SM2-05), showing several possible jumps from Ribos through the surrounding systems. Admiral Wolf says that although there are dozens of star systems accessible from Ribos, the GTA can't afford to give up one more inch to the Shivans.
Is seen in Enter the Dragon (SM2-07) and in Playing Judas (SM2-08), showing the Lucifer jumping from Ribos to Vega and the Galatea jumping from Beta Aquilae to Sol to Deneb. In Enter the Dragon, Admiral Wolf says that fighter patrols have detected advance ships from the Lucifer fleet approaching Vasuda Prime. In Playing Judas, Admiral Wolf says that the Galatea has entered Deneb to guard the system against the Deneb prong of the Shivan attack on Vasuda.
These connections are mentioned but are not shown visually.
Mentioned in The Field of Battle (SM1-02). Admiral Wolf says that Vasudans have been conducting strikes on Terran convoys en route to the Betelgeuse-Antares jump point. This jump corridor may also be alluded to in Paving the Way (SM1-06) when Admiral Wolf says that standard procedure would have the Galatea circumvent the Antares-Beta Cygni jump corridor and make two jumps. Jumping from Antares to Betelgeuse to Beta Cygni would satisfy this requirement. (But so would Antares to Ribos to Beta Cygni, through the pseudocanon Ribos-Beta Cygni corridor.)
These connections are only implied, not described or illustrated.
Implied in Tenderizer (SM2-05). Admiral Wolf says that the Galatea will be moving to Beta Aquilae in case the Shivans decide to attack Vasuda Prime through there. This implies that there is a jump corridor from Beta Aquilae to Vasuda. The shortest alternate route, starting from Beta Aquilae, involves three jumps: Vega to Deneb to Vasuda, or Sol to Deneb to Vasuda. (Of course, since they start in Antares, the Shivans could simply pulverize the Terran blockade and jump directly to Vasuda, but for whatever reason they don't decide to do that.)