Your "fix" is a disaster, the checkpoint you added is on a shorter chain with less work, which is why the blockchain keeps freezing. In other words you are trying to make a bad fork the official one through checkpoints, but this doesn't work because there is a concurrent chain that is longer and has more work (thus, it is the official one by Bitcoin rules). The right chain currently has 793,710 blocks:

Block 786,082 is 6bd72a326b976b882bbdf68051b7cabcfcbdb2ac9c16d5b8a362bfa00716c13b
Block 785,950 is cd1869dba1d23e0b1f9dad0ce7c8ec21c25770f7f9f9fa2beca045f7ffa1b9a9
Block 785,863 is d343df4810bdb2f89f2b3bcfa04ad8131557bbb1fab312d477f7f947fabb0b6c

Now the coin has a deep fork because of the bad checkpoints you added and it's going to revert a ton of transactions with 1500+ confirmations