What problems ? All interested parties want it to remain an open border so it shouldn't be much of a problem.
Hand them an agreement which says something like - "The UK Govt. will commit to keeping the border open on the proviso that the Dublin Govt. take responsibility to prevent illegal immigration at the border, to prevent terrorists popping over the border to commit atrocities as they used to, and to prevent the smuggling problem from becoming much more severe than it always has been.
If the Dublin Govt. fails in its undertaking in these matters, the UK Govt. reserves the right to take measures to protect the UK and its citizens".
There ya go.Job done.
Its actually a red herring. The EU are using it as a shit stirrer to create a problem among the disagreeing parties in the UK, and Dublin are more than willing to help, as it not only helps the EU cause, but gives them a glimmer of hope of driving a wedge between Norn Irn and Great Britain. An opportunity that they will never turn down.
The veiled treat of the issue derailing "the peace process" and thus returning to the murder and maiming of the past is nothing short of sick, and those in Brussels, Dublin, Belfast and Westminster who are indulging in it should be ashamed of themselves, except they are the kind of worthless specimens who are beyond shame.
Whatever the outcome, it wont affect the "peace process", for the same reasons the process came about in the first place.