Michelle Najlis is a writer with two books of poetry, "The Armed Wind" and "Omens," to her credit. Until last year, she was a professor of literature at the University of Costa Rica in San Jose.

Today, Michelle Najilis is in charge of Nicaragua's new Department of Migration, with offices in the National Palace here. Hers is one of the busiest and most sensitive jobs in this country's new revolutionary government.

Najlis' department is busy because thousands of Nicaraguans want to leave the country now that the civil war is over.

Although many are relatives of supporters of former president Anastasio Somoza who are now in exile, the majority want to leave to find work in neighboring Costa Rica or Honduras, want to return to their studies in the United States or Mexico, to take delayed business trips or simply to spend time with family members abroad.

The job is sensitive because the new government here does not want to appear to be restricting the right of emigration of travel, which might give the unwanted appearance of the beginnings of a totalitarian state. At the same time, the Sandinista-backed junta is determined to stop certain Somoza supporters from leaving Nicaragua.

Since last Wednesday, when Nicaragua's revolutionary government began making good on its promise to let any Nicaraguan - except persons wanted for war crimes committed under the Somoza government - leave the country, it has been Najlis' responsibility to sort through more than 300 requests for exit permits daily.

She and the 25 employes who work under her must match the requests against a list of names of persons forbidden to leave Nicaragua for political reasons. The current system is somewhat haphazard, and she acknowledges that it would be relatively easy to falsify the documents required for an exit visa. But she said proudly in an interview today that, so far, her coworkers have identified five persons wanted for political reasons who were seeking permission to leave Nicaragua.

"We know that many Somoza supporters want to leave," she said, "and we have no objection. What we don't want to do, however, is export criminals."

Although Najlis refused to say how many names appear on the list restriction on relatives who want to join self-exiled Somoza supporters or former members of the National Guard who escaped to Honduras or the United States at the end of the war.

But the new government's policy is to stop those it considers war criminals, especially former guardsmen accused of torturing or killing Sandinistas or their supporters, from escaping Nicaraguan justice - although Interior Minister Tomas Borge has said it will not include the death penalty, even for those found guilty of murder.

Although the new government has not begun formal trials yet, it has named a number of new judges who will begin work shortly. It also has begun releasing National Guard prisoners, mostly privates and low-ranking officers whom it does not consider to have committed war crimes before Somoza's fall last month.

One of 269 such military prisoners released today was retired Col. Carlos Eddie Monterrey, who in 1934, on orders of Somoza's father, Gen. Anastasio Somoza Garcia, fired the shot that killed Augusto Cesar Sandino, for whom the Sandinista revolution is named.

The first group of these former National Guard soldiers was released Sunday in an emotional ceremony here, with Borge presiding.

Approximately 220 guardsmen who had been captured and held in the small town of Jinotega since the war ended in mid-July were turned over to the International Red Cross, given safe-conduct passes and told by Borge that they were free to return to their homes. Most of them said they would remain in Nicaragua.

For those and any other Nicaraguans who want to leave, an exit permit issued by Najlis is required. In order to obtain it, a citizen must first find three witnesses to vouch for his personal data and then obtain the signature of the head of his neighborhood Sandinista defense committee and the Sandinista military authority in his city or region.

Since the Department of Migration has only one office, in Managua, persons living outside the capital must come here to obtain the required form, return to their city to have it signed by the local Sandinists authorities, return to Managua to hand it in, wait at least five days for the permit to be issued and then return here for a passport and the official stamp allowing them to leave.

The lines at the National Palace have been long since last week, when this procedure begun. Today, hundreds of people in various stages of the process waited patiently, often for hours, for their permit requests to be processed.

"We hope to issue new passports that will not require exit permits each time a traveler wants to go abroad. Maybe within a few months," Najlis said.

"We have made a revolution," she said apologetically. "But we have not eliminated bureaucracy and red tape. Not yet." CAPTION: Picture, Nicaragua's Interior Minister Tomas Borge, right, walks past a truck with former Somoza troops who were released. UPI