Everything looked good and then Ukraine had the maiden revolution and Russia ended up taking over Crimea. This scared a lot of money out of Ukraine and Cub Energy suffered as well. To further compound issues Russian speaking separatists in Eastern Ukraine declared their independence which led to a state of warfare.
This had a two part effect as half of Cub Energy's properties are in eastern Ukraine but not in the actual conflict zone. In addition, the government of Ukraine, in a stupid attempt to raise revenue for the war, increased oil and gas royalties to 55%. This basically choked off any further investment by any oil and gas explorers in Ukraine. Cub reacted by securing all exploration efforts to conserve cash as it would uneconomical to explore with these onerous royalty rates.
The war, along with the already developing economic issues that Ukraine was experiencing basically led to a near depression in the economy and a collapse of the Ukrainian currency, the hyrvna. This forced the government in Ukraine to seek financial assistance from the IMF. As a condition of the assistance that the IMF agreed to it also forced pro-market reforms on the Ukraine government. One of these was the lowering of oil and gas royalties back to there pre-conflict rate of 29% as stated in this Cub Energy press release.