I've been doing some reading on Sanusia, and it seems that we've shortchanged them in TGW.
First, a country description:
The Sanusi (or Senussi) Religious Order was founded by the noted Islamic religious scholar Mahommed ben Ali ben es Senussi in 1835. At its height in the 1880s, the order controlled most of the interior of North Africa and dominated the north-south trade routes across the Sahara. However, after a confrontation with the Ottoman government in 1894 sheik Senussi el Mahdi withdrew his headquarters to the remote oasis of Kufra, safe from outside interference. The last twenty years have seen the Order's influence shrink as the British and French extend their colonial power into areas once dominated by the Sanusi. In 1911 came a greater blow: the Italian war with the Ottoman Empire. The Italians quickly occupied the major Turkish ports in North Africa, but were unable to penetrate far inland. Nevertheless, the peace treaty of 1912 handed the whole area over to Italy. The undefeated Turkish troops in the region, unwilling to surrender, defected en masse to the Sanusi, bringing with them a nucleus of trained troops and modern weapons including artillery. In November 1912 the Sanusi leader Ahmad ash-Sharif swore to drive out the Italians and restore Muslim rule to the whole of Libya. Maps printed in Europe may show a vast Italian-controlled empire in North Africa; but at the start of 1914 the reality is that the Italians are now hemmed into a narrow coastal strip by the Senusi army. Will the forces of Islam be able to drive the Europeans into the sea? Or will the greater technological might of Italy and their divide-and-conquer tactics weaken the Sanusi forces and lead to their ultimate defeat?
Second, an OOB. In August 1914 they apparently had no fewer than 14 brigades (7 divisions) of troops! These included the Fezzan and Riyah cavalry brigades, and the Jofra, Sirti, two Fezzan, two Riyah and six Tripolitanian infantry brigades. I suggest representing these as a cavalry division (Fezzan/Riyah Division), 1890 Infantry Division (Jofra/Sirti Division), three 1860 Militia Divisions (Fezzan Division, Riyah Division, Tripolitania Division) and two 1890 Garrison Divisions (2nd and 3rd Tripolitania Divisions).
Italy, incidentally, had the following troops in Libya, which ! don't think are in their current TGW OOB:
Libia Division (1912 Light Infantry with attached brigade - artillery, heavy weapons, something like that. Elite.) In Tripoli.
Taranto and Udine Brigades (combine them into one 1895 Infantry division) In Homs.
Tripolitania Division (1900 Militia division - native levies) In Zuara.
Regio Corpo dell Truppe Coloniali della Tripolitania (1890 Light Infantry Division). 50% strength, 15% organisation. In Socna.
Regio Corpo dell Truppe Coloniali della Cyrenaica (1890 Light Infantry Division). In Bengazi.
Possibly a garrison unit in Derna or Tobruk.
Finally, borders. I'd give them the following in 1914: (Italy and Britain should have claims over their respective Sanusi-held territory).
By 1916 the Sanusi held all of the following, after inflicting several defeats on the Italians, driving them back to the coast, and expanding into the French Sudan:
I'd give them claims over all the provinces occupied plus all bordering provinces except that British one in northern Nigeria and the Quattara Depression in Egypt. I'm not sure what to do about the Tuareg tribes in Air: from what I can see, they were subdued and garrisoned by the French in 1914 but rose up as allies of the Sanusi in 1916. In which case, I think representing Air as independent in 1914 isn't accurate; instead the province should be French but with a high resistance factor. The same goes for all the non-coastal provinces of Morocco, incidentally.